The relative decrease change. Definition:
The relative decrease change is the difference in an indicator over two periods in time, v1 - v2, relative to the value of the indicator in the earlier period, v1.
- Where:
- v1 - is called the reference value (original, initial number);
- v2 - is called the new value (the end value).
- In our case: v1 = 0.747, v2 = 0.811.
The relative decrease change. Formula:
The relative decrease change =
The actual change / |v1|
(v1 - v2) / |v1| =
- Legend:
- v1 - the original number
- |v1| - the positive value of v1, |v1| >= 0. By example: |10| = 10; |-10| = 10.
- v2 - the new value
- The actual change = v1 - v2
- / - the fraction bar (division)
Why do we use |v1| in the formula instead of v1?
- Let's see what happens if we use v1 instead of |v1|:
- Choose a random negative number as the initial value: - 53.
- Choose a random positive number for the end value: 13.
Formula and calculation:
(v1 - v2) / v1 =
(- 53 - 13) / - 53 =
-66 / - 53 ≈
1.245283018868 ≈
1.25
Although the absolute difference is negative: -66, the relative decrease change is positive: 1.25. By using |v1| instead of v1, the error is corrected.
The relative percent decrease change. Detailed calculations below
By multiplying a number by the fraction 100/100,
we change only the form of the result, not the result.
- 100/100 = 100% = 100 ÷ 100 = 1.
- n × 100/100 = (n × 100)/100 = (n × 100)%, any number.
The relative percent decrease change. Formula:
The relative percent decrease change =
The relative decrease change × 100/100 =
(The relative decrease change × 100)/100 =
(The relative decrease change × 100)%
Calculate the relative percent decrease change:
(0.747 - 0.811)/|0.747| =
- 0.064/0.747 =
- 0.064 ÷ 0.747 =
- 0.064 ÷ 0.747 × 100/100 =
(- 0.064 × 100 ÷ 0.747)/100 =
(- 6.4 ÷ 0.747)/100 ≈
- 8.567603748327/100 =
- 8.567603748327% ≈
- 8.57%
(Rounded off to max. 2 decimal places)
The relative percent decrease change
from the original, initial value 0.747 to the final, end value 0.811:
Rounded off to max. 12 decimal places ≈ - 8.567603748327%
Rounded off to max. 2 decimal places ≈ - 8.57%
The absolute (actual) difference
0.747 - 0.811 = - 0.064 ≈ - 0.06
By what percentage has 0.747 decreased?
Answer: By ≈ - 8.57%
By what percentage is 0.811 smaller than 0.747?
Answer: By ≈ - 8.57%
The relative percent decrease change is negative,
so in this case we really have a relative percent increase instead
(the value goes up).