Find each percent of change.
1. 40 to 26
2. 75 to 81
3. 25 to 19
4. 68 to 34
5. 45 to 18
6. 50 to 29
7. 64 to 48
8. 50 to 73
9. 65 to 52
10. 25 to 28
11. 80 to 56
12. 50 to 51
13. 15 to 21
14. 60 to 63
15. 50 to 43
16. 50 to 58
17. 75 to 51
18. 12 to 3
19. 20 to 36
20. 80 to 24