| Schedule of quarterly financial information |
| | | | | | | | | | | | | | | | | | | | | | | | | | | First Quarter | | Second Quarter | | Third Quarter | | Fourth Quarter | | | 2019 | | 2018 | | 2019 | | 2018 | | 2019 | | 2018 | | 2019 | | 2018 | Total revenue | | $ | 1,403,630 | | $ | 1,293,403 | | $ | 1,664,277 | | $ | 1,522,174 | | $ | 1,913,851 | | $ | 1,858,356 | | $ | 1,480,618 | | $ | 1,381,193 | Operating income | | $ | 158,296 | | $ | 167,053 | | $ | 308,681 | | $ | 292,152 | | $ | 511,724 | | $ | 550,276 | | $ | 199,376 | | $ | 209,580 | Net income | | $ | 118,157 | | $ | 103,155 | | $ | 240,190 | | $ | 226,676 | | $ | 450,584 | | $ | 470,378 | | $ | 121,297 | | $ | 154,634 | Earnings per share: | | | | | | | | | | | | | | | | | | | | | | | | | Basic | | $ | 0.54 | | $ | 0.45 | | $ | 1.11 | | $ | 1.02 | | $ | 2.10 | | $ | 2.12 | | $ | 0.57 | | $ | 0.70 | Diluted | | $ | 0.54 | | $ | 0.45 | | $ | 1.11 | | $ | 1.01 | | $ | 2.09 | | $ | 2.11 | | $ | 0.56 | | $ | 0.70 |
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