| Financial incentives | 34 % |
| Career path to paid position | 27 % |
| Tax breaks or pensions | 26 % |
| Sense of altruism | 13 % |
| Total | 93 |
| Financial incentives | 34 % |
| Career path to paid position | 27 % |
| Tax breaks or pensions | 26 % |
| Sense of altruism | 13 % |
| Total | 93 |