To calculate the percentage change from 145 to 100, we need to follow the below steps:

Step 1: Find the difference between the two numbers. In this case, the difference is 145 - 100 = 45.

Step 2: Divide the difference by the original number (145) and multiply by 100 to get the percentage change. So, (45/145) x 100 = 31.03%.

Step 3: Since the percentage change is negative, it means there is a decrease in the value. Therefore, the output is 31.03% decrease from 145 to 100.

In conclusion, the percentage change from 145 to 100 is a decrease of 31.03%. This means that the value has decreased by 31.03% from its original value of 145.