| In millions, except per share items | Jun-30-23 | Dec-31-22 | Jun-30-22 | Mar-31-22 | Dec-31-21 | Sep-30-21 | Jun-30-21 | Mar-31-21 |
| | 10-Q | 8-K | 10-Q | 10-Q | 10-K | 10-Q | 10-Q | 10-Q |
| Net income | | | 37.7 | 46.5 | 56.6 | 58.9 | 51.5 | 34.7 |
| Depreciation and amortization | | | 12.8 | 12.2 | 11.7 | 11.4 | 11.2 | 11.2 |
| Stock-based compensation | | | 8.5 | 7.5 | 7.0 | 6.6 | 6.4 | 6.7 |
| Deferred taxes | | | 0.0 | 0.0 | 0.0 | | 0.0 | 0.0 |
| Change in working capital [+] | | | -20.5 | -20.5 | -20.5 | -0.1 | 0.0 | 0.0 |
| Accounts receivable | | | | | -14.3 | | | |
| Inventories | | | | | -10.1 | | | |
| Income taxes | | | -0.1 | -0.1 | -0.1 | 0.1 | 0.2 | 0.2 |
| Other | | | | | 4.0 | | | |
| Other operating activities | | | 1.3 | -4.4 | -0.4 | -17.3 | -7.9 | 0.9 |
| Cash from operations | | | 39.7 | 41.3 | 54.4 | 59.6 | 61.1 | 53.5 |
| |
| Capital expenditures | | | -68.9 | -61.2 | -47.8 | -42.8 | -35.7 | -34.9 |
| Purchases of property and equipment | | | -68.9 | -61.2 | -47.8 | -42.8 | -35.7 | -34.9 |
| Purchases of short-term investments | | | | | -70.9 | | | -100.9 |
| Purchases of short-term investments | | | | | -70.9 | | | -100.9 |
| Other cash from investing | | | | 95.0 | 75.0 | 50.0 | 29.9 | 4.9 |
| Cash from investing | | | -18.9 | 13.6 | -43.7 | -93.6 | -106.7 | -130.9 |
| |
| Option exercises | | | 7.5 | 9.0 | 10.2 | 9.4 | 9.0 | 14.6 |
| Other cash from financing | | | 14.9 | 17.9 | 20.3 | 18.5 | 17.7 | 29.1 |
| Cash from financing | | | 7.4 | 8.9 | 10.1 | 9.2 | 8.7 | 122.1 |
| |
| Free cash flow | | | -29.1 | -19.9 | 6.7 | 16.8 | 25.4 | 18.6 |
| Per share (diluted) | | | ($0.65) | ($0.44) | $0.15 | $0.38 | $0.57 | $0.42 |
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