This paper examines whether industry efforts to decrease managerial discretion, increase uniformity, and improve transparency of a non-GAAP performance measure change voluntary disclosure and market perceptions. We find that the frequency of REITs meeting or beating analysts' expectations of funds from operations (FFO) decreases following explicit industry initiatives to discourage manipulation. Concurrent with this shift, we find that the information content of FFO to investors increased, particularly for firms reporting a reconciliation of FFO with GAAP earnings. We also examine firms in other industries to assess alternative explanations for these results, such as SEC intervention. Collectively, our findings suggest that industry guidance about non-GAAP performance curtailed managers' opportunistic reporting. Furthermore, the market response to FFO is consistent with investors perceiving less manipulation and greater reliability. Our evidence also supports the SEC's subsequent requirement that all non-GAAP disclosures be reconciled to the nearest GAAP measures.