| EU (%) | Merriam and Keller (1978) [17] ; Kumari et al. (2018) [18] | Capra and Scicolone (1998) [19] |
| <66 | Poor | Low |
| 66 - 70 | Poor | Mean |
| 70 - 79 | Acceptable |
|
| 80 - 84 | Good |
|
| 84 - 90 | Good | High |
| 90> | Excellent |
|