| In millions, except per share items | Jun-30-23 | Mar-31-23 | Dec-31-22 | Sep-30-22 | Jun-30-22 | Mar-31-22 | Dec-31-21 | Sep-30-21 |
| | 10-Q | 10-Q | 10-K | 10-Q | 10-Q | 10-Q | 10-K | 10-Q |
| Net income | -22.9 | -16.5 | -21.9 | -21.9 | -19.5 | -18.0 | -14.6 | -10.8 |
| Depreciation and amortization [+] | 0.2 | 0.2 | 0.2 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 |
| Depreciation | 0.2 | 0.2 | 0.2 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 |
| Asset impairment charges | 4.1 | | | | | | | |
| Stock-based compensation | 2.6 | 2.7 | 2.7 | 2.5 | 2.1 | 3.3 | 2.7 | 1.3 |
| Change in working capital [+] | -3.2 | -4.8 | 1.1 | 5.5 | 3.4 | -0.4 | -1.0 | 1.3 |
| Other current assets | 0.6 | -0.1 | -1.8 | 1.8 | 0.7 | -0.6 | -1.6 | -0.1 |
| Other | -3.8 | -4.8 | 2.9 | 3.7 | 2.7 | 0.1 | 0.6 | 1.4 |
| Other operating activities | 0.4 | 0.2 | 1.1 | -0.5 | 0.1 | 0.0 | 0.0 | 0.0 |
| Cash from operations | -18.8 | -18.2 | -16.9 | -14.3 | -13.8 | -15.1 | -12.8 | -8.1 |
| |
| Capital expenditures | -2.8 | -1.6 | -2.0 | -0.8 | -1.4 | -0.2 | -0.2 | -0.2 |
| Purchases of property and equipment | -2.8 | -1.6 | -2.0 | -0.8 | -1.4 | -0.2 | -0.2 | -0.2 |
| Sales of short-term investments, net [+] | 8.5 | 5.1 | -13.3 | | | | | |
| Purchases of short-term investments | | -3.9 | -13.3 | | | | | |
| Sales of short-term investments | 8.5 | 9.0 | | | | | | |
| Other cash from investing | | | | 0.8 | | | | -0.1 |
| Cash from investing | 5.7 | 3.4 | -15.3 | -0.1 | -1.4 | -0.2 | -0.2 | -0.4 |
| |
| Issuance of common stock, net | 15.0 | 5.7 | 8.4 | 0.6 | 0.4 | 50.2 | 0.6 | 0.1 |
| Financing costs | 0.0 | -0.1 | | 0.0 | | | | |
| Other cash from financing | 0.4 | -0.3 | -0.2 | 0.3 | -0.1 | -0.1 | | |
| Cash from financing | 15.4 | 5.5 | 8.2 | 1.0 | 0.2 | 50.1 | 0.6 | 0.1 |
| |
| Free cash flow | -21.6 | -19.9 | -18.9 | -15.1 | -15.2 | -15.3 | -13.0 | -8.3 |
| Per share (diluted) | ($0.09) | ($0.09) | ($0.09) | ($0.07) | ($0.07) | ($0.07) | ($0.07) | ($0.04) |
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