Reusable Cups Research Articles

Probabilistic rewards increase the use of reusable cups

Given the environmental threat posed by single-use disposable cups, increasing the use of reusable cups among consumers is vital. To achieve this goal, the current study examined how probabilistic rewards influenced the use of reusable cups at cafés on a university campus. In the pilot study, customers with reusable cups were offered a 5 % chance to win a $5 gift card. This probabilistic reward produced a significant increase in the use of reusable cups compared to baseline. In a separate field experiment, one café offered customers with reusable cups a 10 % chance to win a free coffee, while another café served as a control site without the reward. The probabilistic reward led to a significant increase in the use of reusable cups. Together, these findings provide initial support for the implementation of probabilistic rewards to increase the use of reusable cups, with empirical, theoretical, and practical implications for sustainable consumption.

Exploratory analysis of influential factors in the choices of using single-use or reusable cups in vending

PurposeThis study investigates the variables that play a role in the purchase intention of a hot beverage at a vending machine (1) served in a 100% recyclable plastic single-use cup, (2) served in a biodegradable paper single-use cup and (3) served in personal, reusable cups brought by customers. The variables considered are perceived environmental benefits (PEBs), perceived contamination risk (PCR), social norms (SNs), value for money (VM), gender and age. The secondary objective is to investigate respondents’ perceptions of these cups using the first four variables and to assess the existence of significant differences among them.Design/methodology/approachFor the first purpose, three separate logistic regression models on purchase intention were created, considering PEBs, PCR, SNs, VM, gender and age as independent variables. For the second purpose, the analysis relied on Friedman’s nonparametric test. The entire survey was conducted in Italy on a sample of 1,006 consumers.FindingsSNs and VM are the variables with the greatest influence on final purchase intention. PEBs seem to have an effect only in the case of the plastic and paper single-use cups, while PCR only in the case of the reusable cup. Neither gender nor age seem to play a significant role in final purchase intention. Friedman’s test revealed significant differences among the three cup types in terms of perceptions, but not in the case of the PCR variable.Originality/valueThe study is the first to compare new single-use cups with reusable cups from vending machines in terms of consumers’ perceptions and preferences.

One Year of Mandatory Reusable Packaging in Germany: Opportunities and Obstacles from the Perspective of Consumers and Companies

Since the beginning of 2023, the so-called reusable packaging obligation has been in place in Germany in order to reduce the amount of waste from takeaway packaging. Catering companies will then be obliged to offer reusable packaging as an alternative to disposable plastic takeaway packaging. As part of the pilot project ‘Mehrweg Modell Stadt’ (‘Reusable city model’), an open infrastructure for reusable cups is in trial in Mainz and Wiesbaden. The project was subjected to a scientific monitoring process, which included the implementation of quantitative surveys among various stakeholders within the value chain, namely consumers, catering companies, and other companies engaged in the project. This was conducted over two time periods: August 2023 to September 2023, and February to March 2024. The results show a discrepancy between consumers’ attitudes and their actual behavior: Despite a high level of sustainability awareness and perceived positive benefits of reusable packaging, perceived barriers stand in the way of actual use. The biggest challenges for companies are the lack of consumer demand, practical handling and hygiene requirements. The results of this quantitative social research provide important insights for the development of targeted measures to promote the use of reusable packaging in takeaway catering and contribute to the discussion on closing the attitude–behavior gap along the entire value chain.

THE REUSABLE COFFEE CUP SYSTEM “BILLIE CUP” IN A UNIVERSITY SETTING: A PILOT-STUDY

500 billion disposable cups are consumed every year and contribute to polluting the natural environment. Reusable cups offer a reasonable alternative, especially in work or study places with efficient and sustainable washing facilities. In one coffee bar at a university building, disposable cups were completely banished and a reusable polypropylene cup, the so-called “Billie Cup”, was introduced together with automated deposit and washing facilities. Quantitative and qualitative analyses were performed to measure financial differences, waste reduction, and customer opinion. After introduction of the Billie Cup, we reduced approximately 2.5 kg of waste per week and did not report significant changes in weekly sales [median: 336 (interquartile range: 291–359) vs. 337 (297–349) drinks, respectively, P=1.000] or revenue [578 (492–612) vs. 576 (492–586) euro, respectively, P=0.833]. Furthermore, we reported significantly higher numbers of refilling a cup with a median of 21 (16–25) vs. 43 (38–59) drinks per week, respectively, P=0.017. Resulting from our questionnaires, we found that all respondents believed that disposable cups produce unnecessary waste on campus. Our pilot study demonstrates that a reusable coffee cup system along with banishing all disposable cups can be successfully implemented without decreasing monthly revenue or sales.

The Effect of Brand Lovemark on Reusable Cups in Coffee Shops: Machine Use Intention, Willingness to Pay a Deposit, and Green Brand Loyalty

Despite significant coffee shops’ efforts to promote sustainable practices, customers’ actual CSR engagement in the coffee shop industry is still low. This is because CSR practices in the hospitality industry often require customer engagement, which can sometimes be inconvenient for customers, and some customers may even be skeptical about green practices themselves. Thus, this study examines the effect of brand lovemark on three customer behavioral outcomes (i.e., green brand loyalty, willingness to pay a deposit, and machine use intention) in coffee shops’ CSR practices. We used a scenario-based experimental design on CSR practices in two coffee shop brands (i.e., Starbucks and Dunkin’). The study demonstrates that consumers with a high brand lovemark act more positively toward coffee shop CSR practices than customers with a low brand lovemark. In addition, the interactions between brand lovemark and gender appear to be important in all three behavioral outcomes. Specifically, it confirms that men and women show different levels of behavior outcomes depending on their level of brand lovemark. Theoretical and managerial implications are also suggested with the direction for future study.

Transitioning beyond single-use plastic drinks cups: an emergent social marketing case study in Scotland

PurposeThis study aims to investigate whether consumers and small businesses can transition from disposable to reusable coffee cups, using a community social marketing intervention, led by a Social Purpose Organisation.Design/methodology/approachAn emergent case study approach using multiple sources of data developed an in-depth, multifaceted, real-world context evaluation of the intervention. The methodology draws on citizen science “messy” data collection involving multiple, fragmented sources.FindingsMoving from single-use cups to reusables requires collective commitment by retailers, consumers and policymakers, despite the many incentives and penalties applied to incentivise behaviour change. Difficult post-COVID economics, austerity and infrastructure gaps are undermining both reusable acceptance and interim solutions to our dependence upon disposables.Research limitations/implicationsAlthough the non-traditional methodology rendered gaps and omissions in the data, the citizen science was democratising and inclusive for the community.Practical implicationsOur practical contribution evaluates a whole community intervention setting to encourage reusable cups, integrating multiple stakeholders, in a non-controllable, non-experimental environment in contrast to previous research. This paper demonstrates how small community grants can foster impactful collaborative partnerships between an SPO and researchers, facilitate knowledge-exchange beyond the initial remit and provide a catalyst for possible future impact and outcomes.Originality/valueTo assess the impact at both the outcome and the process level of the intervention, we use Pawson and Tilley’s realist evaluation theory – the Context Mechanism Outcome framework. The methodological contribution demonstrates the process of citizen science “messy” data collection, likely to feature more frequently in future social science research addressing climate change and sustainability challenges.

A tasty solution to packaging waste? Life cycle assessment of edible coffee cups

Edible cups have been proposed as a solution to littering and plastic pollution arising from disposal of 500 billion beverage cups each year. We applied life cycle assessment and a littering indicator to benchmark the environmental performance of edible cups against mainstream cup types made from paper, polylactic acid (PLA), polystyrene (PS) and reusable cups made from polypropylene (PP) and steel. Various end-of-life treatment scenarios were analysed. Across most impact categories, edible cups incur the largest burdens, and reusable cups the smallest (if reused at least 54 times). Under default assumptions, per cup use, climate change burdens ranged from 0.004 to 0.1 kg CO2 equivalent, eutrophication burdens ranged from 6.26 × 10–6 to 4.21 × 10–4 kg N, fossil resource depletion burdens ranged from 0.05 to 0.284 MJ and water depletion burdens ranged from 0.002 to 0.437 m3. However, if edible cups are eaten after use and substitute a similar snack then their use could incur negligible environmental impact. Furthermore, edible cups demonstrate low littering potential and thus could play a role in transition towards more sustainable coffee consumption.

Green university initiatives and undergraduates’ reuse intention for environmental sustainability: The moderating role of environmental values

Environmental sustainability is an important issue today. It is harmful to the environment to use single-use cups. Therefore, the research aims to investigate undergraduates' reuse intentions about using reusable drinkware on campus. The study used an updated theory of planned behavior (TPB) model by incorporating moral norms, green university initiatives, and environmental values as new components. A convenient sampling method is applied to collect the data. A total of 337 responses were collected from university undergraduates. For testing various relations, this study employed structural equation modeling. The outcomes support that moral norms and all TPB constructs influence students' intention to reuse reusable cups, and behavioral control has the highest impact. Green university initiatives significantly predict moral norms and TPB constructs. Environmental value moderates the association between moral norms and reuse intentions. The outcomes of this research will help policymakers and university authorities create plans for teaching and motivating students about the environment and encouraging green behavior for environmental sustainability.

Decreasing consumption of sugar-sweetened beverages and Raising tap water consumption through Interventions based on Nutrition and sustainability for Kids: study protocol of the “DRINK” cluster randomised controlled trial

BackgroundEffectiveness of actions to reduce sugar-sweetened beverage (SB) consumption in children still needs to be improved. Furthermore, the growing concern about sustainable food systems encourages to develop sustainability-based interventions. The objective of this cluster randomised controlled trial is to evaluate the long-term effectiveness of nutrition- and environmental sustainability-based interventions on the reduction in SB intake and on the increase in tap water consumption in 3rd to 6th grade primary school children (8 to 11 years of age).MethodsForty-eight French-speaking Belgian primary schools (equivalent to around 3500 pupils involved in the evaluation) are randomised using a factorial plan: (i) control, (ii) nutrition-based intervention, (iii) sustainability-based intervention, and (iv) both. The interventions (encouragement of water breaks; provision of posters, leaflets, reusable cups, and glass bottles; website; meetings at school) were undertaken from February 2022 to June 2023. Evaluation includes questionnaires for the children and their parents on various determinants of dietary behaviour, a 4-day diary to collect information on the child’s beverage consumption, and audits at schools. The first evaluation was conducted in Spring 2021 before any intervention, with the two post-intervention evaluations being held in 2022 and 2023. The main quantitative judgement criterion will be the change over time in the mean SB consumption (in ml/day) in the intervention groups compared with the control group. Given the context of the research (school), the safety of the intervention, and the content of data collection, a consent was acknowledged as unnecessary by the Ethical Committee of the Faculty of Psychology (ULB; n°073/2021), but children and parents are explicitly informed of their right to refuse to fill in the questionnaires.DiscussionMulticomponent interventions based on nutrition and on environmental sustainability, alone or mixed, will provide an original and topical insight into health promotion at school around dietary behaviours. The dissemination plan will enable to widely inform stakeholders, school staff, and families, in addition to the scientific community through the usual medium (articles, conferences), about the research findings in 2024–2025.Trial registrationISRCTN Registry ISRCTN99843102. Retrospectively registered on 25 May 2021

Acceptability of a behaviour change intervention aimed at increasing the use of a reusable hot drink cup

Plastic pollution is an acute issue, with single-use plastic contributing to it significantly. It is beneficial for the planet if we engage in more sustainable behaviors, such as using reusable items instead of single-use ones, thus reducing plastic pollution. We implemented an intervention to increase the use of reusable coffee cups, by employing behavior change techniques that targeted values towards environment, intention to use a reusable cup, and habit. The intervention was successful in increasing the participants’ use of reusable cups. The aim of the current study was to evaluate the acceptability of the intervention and research methods, as well as opinions of participants about the process and intervention effectiveness, using a mixed methods approach. Participants (N = 156) answered open and closed survey questions about the acceptability of the intervention, and 11 participated in interviews regarding their experience of intervention. The intervention was deemed acceptable and useful by all participants, regardless of which intervention condition they were allocated to, according to both survey and interview data. Men, however, evaluated the intervention as less personally relevant than women, with overall participation of men in the intervention being smaller than women. Recommendations for implementing similar interventions and future research are offered.

Green Initiatives and Environmental Concern Foster Environmental Sustainability: A Study Based on the Use of Reusable Drink Cups.

Unsustainable production and consumption have threatened human life and nature. Therefore, practitioners around the globe have paid attention to sustainability issues and adopted pro-environmental strategies to protect the environment. Using single-use cups contributes to environmental pollution. This study aims to understand university students’ intention to use reusable drink cups in university campuses. This study has extended the theory of planned behavior (TPB) model by including moral norms, green university initiatives, environmental concerns, and moral norms. The purposive sampling technique has been employed to collect students’ data from the twelve universities in Pakistan. Partial least square structural equation modeling (PLS-SEM) has been employed to test the hypothesized model. The study’s results revealed that green university initiatives and norms significantly shape students’ intention to use reusable cups. However, environmental concern has an insignificant impact on the perceived behavioral control. This study’s results help higher education institutions to formulate strategies that create awareness among students and promote environmentally sustainable practices.

Comparative life cycle analysis of drinking water supply on a filmset: the case study of ‘Binti’

Quantification of the environmental impact of film production is still under development. Catering for the film crew is estimated to account for 10 to 15% of the total CO2 emission of a production, but specific data on the contribution of the different catering components is largely missing. To partially fill the existing knowledge gap, this study quantifies and compares the environmental impact of drinking water supply on the sets of the Flemish film ‘Binti’. On these sets, drinking water was supplied by means of water dispensers with 15 l mineral water bottles or from the tap in combination with both reusable PP and single-use cardboard cups. The inventory was compiled based on information supplied by the film producer and the equipment suppliers. The environmental impacts were calculated for four different scenarios using the ILCD 2.0 midpoint methodology with a focus on the impact categories of recommendation level I and II. Results show that transportation of the bottled water and the production of the cups had the largest share in the total environmental impacts. Furthermore, the use of a new type of filtered and cooled tap water dispenser made partly of reused and recycled materials, in combination with reusable PP cups, could have reduced by 50% the greenhouse gas emissions of drinking water supply on the ‘Binti’ filmsets. Scenario’s in which only 0.5 l bottles of mineral water or water dispensers with 15 l bottles in combination with reusable cups were used, showed environmental impacts up to 2.5 times higher than in the reference scenario. A more general conclusion is that, to reduce the environmental impact of drinking water supply on their film sets, producers should avoid as much as possible the transport of bottled water by connecting the dispensers to the water mains wherever possible or by using locally bottled water, each time in combination with reusable plastic cups.

Influences on single-use and reusable cup use: a multidisciplinary mixed-methods approach to designing interventions reducing plastic waste

An estimated 2.5-5 billion single-use coffee cups are disposed of annually in the UK, most of which consist of paper with a plastic lining. Due to the difficulty of recycling poly-coated material, most of these cups end up incinerated or put in landfills. As drinking (take-away) hot beverages is a behaviour, behaviour change interventions are necessary to reduce the environmental impacts of single-use coffee cup waste. Basing the design of interventions on a theoretical understanding of behaviour increases the transparency of the development process, the likelihood that the desired changes in behaviour will occur and the potential to synthesise findings across studies. The present paper presents a methodology for identifying influences on using single-use and reusable cups as a basis for designing intervention strategies. Two behaviour change frameworks: The Theoretical Domains Framework (TDF) and the Capability-Opportunity-Motivation-Behaviour (COMB) model of behaviour, were used to develop an online survey and follow-up interviews. Research findings can inform the selection of intervention strategies using a third framework, the Behaviour Change Wheel (BCW). The application of the methodology is illustrated in relation to understanding barriers and enablers to single-use and reusable cup use across the setting of a London university campus. We have developed a detailed method for identifying behavioural influences relevant to pro-environmental behaviours, together with practical guidance for each step and a worked example. Benefits of this work include it providing guidance on developing study materials and collecting and analysing data. We offer this methodology to the intervention development and implementation community to assist in the application of behaviour change theory to interventions.

Improvement of Packaging Circularity through the Application of Reusable Beverage Cup Reuse Models at Outdoor Festivals and Events

Festivals generate huge amounts of waste during a short period of time, usually in three to four days. Single-use packaging is one of the dominant waste streams at the festivals. In order to minimize single-use plastic packaging waste generation and negative impacts on the environment, outdoor festivals apply alternative reusable cup systems and strategies. However, little studies have been made on how different reusable beverage cup reuse models can affect material circularity within certain festivals, and how it contributes to cup damage and loss. This article presents the results of a pilot study of different reusable cup reuse models within seven Lithuanian summer outdoor festivals. Three different models were applied and tested: A—only reusable cups, non-refundable model; B—only reusable cups, with deposit-refund; C—a mixed system of reusable cups with deposit-refund and of single-use cups. Material flow analysis (MFA) was performed, and the Materials Circularity Indicator (MCI), developed by Ellen MacArthur Foundation, was calculated to study the applied models. According to the findings, refund models (B, C models) have lower rates of damaged and lost cups compared to non-refundable reusable cup reuse model (A model). This paper shows that different reuse models provide different damage, loss and return rates of reusable cups. The data presented can aid decision-makers who need to choose a reuse model for a certain event.

Minimizing the Use of Polyethene inside Paper Coffee Cups

Although made of paper, most coffee cups are not recycled because of the polyethene covering their internal surface area (1, 2). Instead, they are sent to landfills where they break down into microplastics and negatively impact organisms after entering the food chain (2, 3). This is an especially alarming issue due to the extensive usage of paper coffee cups around the world. As a result, many global companies have been searching for an eco-friendly cup that eliminates the use of polyethene, a challenge that remains unresolved to this day (9). While the search continues, many businesses have relied on temporary strategies to reduce polyethene production until a design that eliminates its use is developed (9, 10, 11, 12). Two major methods include public awareness and promotion of reusable cups (2). However, these approaches have only resulted in minor changes due to their reliance on customer cooperation (2). To guarantee polyethene reduction, this report proposes a strategy that is independent of customer cooperation. This method determines the dimensions (i.e., height and bottom radius) that minimize the amount of polyethene needed to coat the internal surface area of a cup, while keeping the cup’s volume and lid size (i.e., top radius) the same. The resulting equation gives the surface area of the cup while the root to the first derivate of this equation corresponds to the optimal bottom radius. Using a derived equation for height, the optimal cup height is determined as well. To highlight its proper implementation, this strategy is applied to a Starbucks Grande coffee cup as a model for other companies to follow.

Assessment of the environmental break-even point for deposit return systems through an LCA analysis of single-use and reusable cups

The Circular Economy introduced new research challenges to be faced. Linear and circular supply chain comparisons require general methodologies to obtain significant and scalable results. A two-step methodology is here proposed to facilitate the interpretation of results during a Life Cycle Assessment (LCA). Firstly, an LCA analysis has been conducted on four single-use - Polypropylene (PP), Polylactic acid (PLA), Polyethylene terephthalate (PET), and Cardboard+Polyethylene coat - and reusable - PP, PLA, PET, and glass - cups. Secondly, the analyzed midpoint impact categories have been aggregated into the three main life cycle phases: production, use and End of Life (EoL). Then, they have been used to assess the environmental break-even point (BEP), i.e. the minimum number of uses necessary for a reusable cup to be preferable than a single-use cup, considering two EoL (energy recovery, and recycling) and three use phase strategies (onsite handwashing, onsite and offsite washing). Considering offsite washing - transport distance of 20km and industrial washing machines - and energy recovery, findings highlight that reusable plastic cups reach a break-even point for climate change and non-renewable energy use for n<150, while single-use PP cups are the best option in terms of acidification, eutrophication, and water scarcity indicator. With respect to PP single-use cups, for acidification, eutrophication, and water scarcity indicator, a BEP cannot be achieved, even in the case of infinite reuses. Results evidenced all the conditions for reaching a BEP, allowing to identify possible strategies to improve the efficiency of reusable products and to obtain an environmental benefit.

My cup of tea: Behaviour change intervention to promote use of reusable hot drink cups

Globally approximately 16 billion paper coffee cups are being thrown away every year. One solution to this problem is using a reusable hot drink cup. We developed a behaviour change intervention to increase the use of reusable hot drink cups on an Australian University campus and evaluated its effectiveness; we also investigated the psychological mechanisms through which change happens; moreover, we extended the investigation on the previously established relationship between habit strength and intolerance of uncertainty. Participants (N = 156) from a large Australian University were randomly assigned to one of four intervention conditions: 1) an intervention aimed at evoking environmental values, 2) an intention-based intervention, 3) a habit-based intervention, and 4) a control group with no direct intervention to increase use of reusable cups. At baseline, participants in the three intervention groups received a new reusable hot drink cup, and completed a pre- and six-week post-intervention questionnaire assessing habit strength, intention to use a reusable cup, biospheric values, personal involvement and personal norms towards the environment, ecological worldview, and intolerance of uncertainty. The behaviour of using a reusable cup was recorded by participants using a phone app immediately after delivery of the intervention and at six-week follow-up. There was a significant increase in the use of reusable cups in all intervention conditions immediately after the intervention and after the six-week follow-up, compared to the control condition. The key mechanisms for behaviour change were similar between the intervention conditions, with groups increasing habit strength, especially if they had difficulty tolerating uncertainty. These findings offer suggestions for establishing habits in pro-environmental behaviour change interventions, as well as for tailoring habit-based interventions for those who are intolerant of uncertainty.

Sustainability at a Brazilian university: developing environmentally sustainable practices and a life cycle assessment case study

PurposeSome universities have a commitment to both academic education and sustainable development, and the sustainable development goals can support several sustainable actions that universities may take as principles and attitudes. From this perspective, the purpose of this study is to present environmentally sustainable practices at a federal university in Brazil and to analyze and discuss the potential environmental impacts associated with an environmentally sustainable practice implemented using life cycle assessment (LCA) and its benefits for the university’s decision-makers.Design/methodology/approachTo accomplish that, the study combines a description of environmentally sustainable practices at the 13 campuses of the Universidade Tecnológica Federal do Paraná (UTFPR) in terms of education, water and electricity consumption, waste management and emissions. As a result of this analysis, one campus identified that a high volume of disposable plastic cups were being disposed of, for which the use of reusable plastic cups was introduced. In addition, an LCA study (ISO 14040:2006 and 14044:2006) quantified the benefits of the introduction of said reusable plastic cups.FindingsThe results show that the university is working on environmentally sustainable initiatives and policies to become greener. At the same time, using a systematic LCA made it possible to measure that replacing disposable plastic cups for reusable ones reduced waste generation but increased water consumption on the campus. Faced with this, a sensitization was carried out to reduce water consumption. Finally, the current study provides lessons on the environmental performance to universities interested in sustainable practices, fostering perspectives for a better world. The findings of this study encourage organizations to accomplish environmental actions toward greener universities. The study shows that institutions need to be reflective and analytical about how even “greening” measures have impacts, which can be mitigated if necessary.Practical implicationsThe sustainable practical implications were reported, and an LCA was conducted to assess potential environmental impacts of reusable plastic cups. It was identified that raw material production is the phase that generates most environmental impacts during the life cycle of the product, along with the consumer use phase, due to the quantity of water used to wash the reusable cups. In addition, the practical contributions of this study are to provide insights to institutions that aim to use environmental actions, i.e. suggestions of sustainable paths toward a greener university.Originality/valueThis is one of the first studies to investigate and discuss sustainable practices at UTFPR/Brazil. The study assessed one of the practices using a scientific technique (LCA) to assess the impacts of reusable plastic cups distributed to the students of one of the 13 campuses. Although there are other studies on LCA in the literature, the value of this study lies in expanding what has already been experienced/found on the use of LCA to assess environmental practices in university campuses.

To go or not to go, that is the question: Using social influence to reduce hot beverage cup waste

ABSTRACT While most consumers today feel concerned by environmental issues, the consumption of hot beverage in disposable cups remains very important. In this study, we use influence strategies related to social norms to reduce these behaviors and get consumers to consume their hot beverage in reusable cups. 14373 orders were analyzed and demonstrate that normative messages can be effective to change consumer behavior toward a more responsible choices.

Legacy of the disposable cup

Single-Use Plastics It is estimated that, as a global population, we use between 250 billion and 300 billion disposable cups annually. These cups are mostly composed of virgin tree cellulose coated with plastic and are almost never recycled. Foteinis conducted a life-cycle analysis of disposable cup use, focusing on the United Kingdom, and found that their annual carbon footprint was equivalent to that produced by the manufacture of ∼11,500 midsized cars or that of 1.5 million European residents. Improved recycling could reduce these impacts by up to 40%, and reusable cups would reduce the carbon footprint threefold. Disposable cups represent only a tiny bit of our daily resource use, so these results emphasize just how large an impact our day-to-day activities have on the planet. They also show how much improvement we have the potential to make with small, seemingly inconsequential choices. J. Clean. Prod. 255 , 120294 (2020).