Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
|  |  | Year Ended December 31, | Year Ended December 31, | Percent Increase (Decrease) |
| --- | --- | --- | --- | --- |
|  |  | 2018 | 2017 | (In cents, except percentage changes) |
|  |  | (In cents, except percentage changes) | (In cents, except percentage changes) |  |
| Total CASM: | Aircraft fuel and related taxes | 2.86 | 2.22 | 28.8 |
| Total CASM: | Salaries, wages and benefits | 4.34 | 4.32 | 0.5 |
| Total CASM: | Maintenance, materials and repairs | 0.73 | 0.71 | 2.6 |
| Total CASM: | Other rent and landing fees | 0.67 | 0.65 | 3.1 |
| Total CASM: | Aircraft rent | 0.45 | 0.43 | 3.5 |
| Total CASM: | Selling expenses | 0.54 | 0.53 | 0.9 |
| Total CASM: | Depreciation and amortization | 0.65 | 0.62 | 5.9 |
| Total CASM: | Special items, net | 0.28 | 0.26 | 8.3 |
| Total CASM: | Other | 1.80 | 1.78 | 1.6 |
| Regional expenses: | Aircraft fuel and related taxes | 0.65 | 0.50 | 30.7 |
| Regional expenses: | Other | 1.88 | 1.87 | 0.4 |
| Regional expenses: | Total CASM | 14.85 | 13.88 | 6.9 |
| Special items, net: | Special items, net | (0.28) | (0.26) | 8.3 |
| Special items, net: | Regional operating special items, net | — | (0.01) | nm (1) |
| Aircraft fuel and related taxes | Aircraft fuel and related taxes - mainline | (2.86) | (2.22) | 28.8 |
| Aircraft fuel and related taxes | Aircraft fuel and related taxes - regional | (0.65) | (0.50) | 30.7 |
| Aircraft fuel and related taxes | Total CASM, excluding special items and fuel | 11.06 | 10.90 | 1.4 |
Question:
How much increase is observed for selling expenses on total CASM for American Airlines from 2017 to 2018? 
Answer:
0.9