I found this table here: https://danluu.com/cli-complexity/
| command | 1979 | 1996 | 2015 | 2017 |
|---|---|---|---|---|
| ls | 11 | 42 | 58 | 58 |
| rm | 3 | 7 | 11 | 12 |
| mkdir | 0 | 4 | 6 | 7 |
| mv | 0 | 9 | 13 | 14 |
| cp | 0 | 18 | 30 | 32 |
| cat | 1 | 12 | 12 | 12 |
| pwd | 0 | 2 | 4 | 4 |
| chmod | 0 | 6 | 9 | 9 |
| echo | 1 | 4 | 5 | 5 |
| man | 5 | 16 | 39 | 40 |
| which | 0 | 1 | 1 | |
| sudo | 0 | 23 | 25 | |
| tar | 12 | 53 | 134 | 139 |
| touch | 1 | 9 | 11 | 11 |
| clear | 0 | 0 | 0 | |
| find | 14 | 57 | 82 | 82 |
| ln | 0 | 11 | 15 | 16 |
| ps | 4 | 22 | 85 | 85 |
| ping | 12 | 12 | 29 | |
| kill | 1 | 3 | 3 | 3 |
| ifconfig | 16 | 25 | 25 | |
| chown | 0 | 6 | 15 | 15 |
| grep | 11 | 22 | 45 | 45 |
| tail | 1 | 7 | 12 | 13 |
| df | 0 | 10 | 17 | 18 |
| top | 6 | 12 | 14 |