| In millions, except per share items | Dec-31-20 | Sep-30-20 | Jun-30-20 | Mar-31-20 | Dec-31-19 | Sep-30-19 | Jun-30-19 | Mar-31-19 |
| | 10-K | 10-Q | 10-Q | 10-Q | 10-K | 10-Q | 10-Q | 10-Q |
| Net income | 72.7 | 95.7 | 97.9 | 104.7 | 117.0 | 146.9 | 159.9 | 169.6 |
| Depreciation and amortization [+] | 12.6 | 13.3 | 14.8 | 16.9 | 20.0 | 25.1 | 28.7 | 29.2 |
| Depreciation | 12.6 | 13.3 | 14.8 | 16.9 | 20.0 | 25.1 | 28.7 | 29.2 |
| Stock-based compensation | 56.8 | 44.7 | 45.2 | 43.9 | 46.6 | 44.5 | 75.5 | 49.5 |
| Deferred taxes | -4.7 | -9.1 | -13.5 | -21.0 | -3.0 | 0.1 | 7.9 | 5.1 |
| Change in working capital [+] | -15.3 | -41.6 | -43.6 | -32.9 | 46.6 | 34.3 | 2.1 | -0.6 |
| Accounts receivable | -2.8 | -12.4 | -31.3 | -16.3 | 54.0 | 35.4 | 43.9 | 26.4 |
| Other | -12.6 | -29.2 | -12.3 | -16.7 | -7.4 | -1.1 | -41.8 | -27.1 |
| Other operating activities | 66.0 | 70.7 | 70.8 | 101.2 | -61.2 | -73.6 | 14.4 | 34.9 |
| Cash from operations | 188.0 | 173.7 | 171.6 | 212.8 | 166.0 | 177.5 | 289.9 | 289.3 |
| |
| Capital expenditures [+] | -8.6 | -9.0 | -9.3 | -7.5 | -5.8 | -4.9 | -5.3 | -3.6 |
| Purchases of property and equipment | -8.6 | -9.0 | -9.3 | -7.5 | -5.8 | -4.9 | -5.3 | -3.6 |
| Sales of property and equipment | 2.3 | 2.3 | | | | | | |
| Sales of short-term investments | 173.4 | 141.5 | 155.7 | 156.8 | 161.3 | 140.7 | 204.4 | 107.4 |
| Sales of short-term investments | 173.4 | 141.5 | 155.7 | 156.8 | 161.3 | 140.7 | 204.4 | 107.4 |
| Other cash from investing | -68.4 | -57.3 | -101.1 | -114.6 | -162.4 | -186.1 | -192.7 | -163.7 |
| Cash from investing | 98.7 | 77.5 | 45.3 | 34.8 | -6.9 | -50.4 | 6.4 | -59.9 |
| |
| Cash dividends paid | -65.6 | -67.7 | -69.8 | -72.1 | -74.3 | -76.2 | -119.4 | -79.7 |
| Repurchase of common stock, net | -115.6 | -150.0 | -151.6 | -168.5 | -155.8 | -163.9 | -210.5 | -153.7 |
| Other cash from financing | | 7.7 | 8.4 | 6.2 | 5.6 | -0.7 | -95.0 | -5.9 |
| Cash from financing | -175.5 | -210.0 | -212.9 | -234.4 | -224.5 | -240.9 | -424.9 | -239.4 |
| |
| Free cash flow | 179.5 | 164.7 | 162.3 | 205.3 | 160.2 | 172.6 | 284.6 | 285.6 |
| Per share (diluted) | $2.74 | $2.43 | $2.33 | $2.85 | $2.16 | $2.27 | $3.66 | $3.59 |
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