Input: To calculate the percentage change from 600 to 1000, we need to follow the below steps:

Step 1: Find the difference between the two numbers.

1000 - 600 = 400

Step 2: Divide the difference by the original number (600) and multiply by 100 to get the percentage change.

(400/600) x 100 = 66.67%

Step 3: Determine the direction of the change. Since the output (1000) is greater than the input (600), the percentage change is positive.

Step 4: Interpret the result. The percentage change from 600 to 1000 is 66.67%, which means that the output (1000) is 66.67% higher than the input (600). Alternatively, we can say that the input (600) is 33.33% lower than the output (1000).

In conclusion, the percentage change from 600 to 1000 is 66.67%, indicating a significant increase in the value.