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 = 45.37, v2 = - 9.7.
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: - 38.
- Choose a random positive number for the end value: 80.
Formula and calculation:
(v1 - v2) / v1 =
(- 38 - 80) / - 38 =
-118 / - 38 ≈
3.105263157895 ≈
3.11
Although the absolute difference is negative: -118, the relative decrease change is positive: 3.11. 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:
(45.37 - (- 9.7))/|45.37| =
(45.37 + 9.7)/|45.37| =
55.07/45.37 =
55.07 ÷ 45.37 =
55.07 ÷ 45.37 × 100/100 =
(55.07 × 100 ÷ 45.37)/100 =
(5,507 ÷ 45.37)/100 ≈
121.37976636544/100 =
121.37976636544% ≈
121.38%
(Rounded off to max. 2 decimal places)
The relative percent decrease change
from the original, initial value 45.37 to the final, end value - 9.7:
Rounded off to max. 12 decimal places ≈ 121.37976636544%
Rounded off to max. 2 decimal places ≈ 121.38%
The absolute (actual) difference
45.37 + 9.7 = 55.07
By what percentage has 45.37 decreased?
Answer: By ≈ 121.38%
By what percentage is - 9.7 smaller than 45.37?
Answer: By ≈ 121.38%
The relative percent decrease change is positive,
so we really have a relative percent decrease
(the value goes down).