5. Per Share and Per Unit Data

We determine basic earnings per share and basic earnings per unit based on the weighted average number of shares of common stock or units, as applicable, outstanding during the period and we consider any participating securities for purposes of applying the two-class method. We determine diluted earnings per share and diluted earnings per unit based on the weighted average number of shares of common stock or units, as applicable, outstanding combined with the incremental weighted average number of shares or units, as applicable, that would have been outstanding assuming all potentially dilutive securities were converted into shares of common stock or units, as applicable, at the earliest date possible. The following tables set forth the components of basic and diluted earnings per share and basic and diluted earnings per unit.

Simon

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For the three months ended March 31, 2026, potentially dilutive securities include units that are exchangeable for common stock and long-term incentive performance units, or LTIP units, granted under our long-term incentive performance programs that are convertible into units and exchangeable for common stock. No securities had a material dilutive effect for the three months ended March 31, 2026 and 2025. We have not adjusted net income attributable to common stockholders and weighted average shares outstanding for income allocable to limited partners or units, respectively, as doing so would have no dilutive impact. We accrue dividends when they are declared.  

The Operating Partnership

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For the three months ended March 31, 2026, potentially dilutive securities include LTIP units. No securities had a material dilutive effect for the three months ended March 31, 2026 and 2025. We accrue distributions when they are declared.