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 = 47.43, v2 = 6.2.
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: - 65.
- Choose a random positive number for the end value: 1.
Formula and calculation:
(v1 - v2) / v1 =
(- 65 - 1) / - 65 =
-66 / - 65 ≈
1.015384615385 ≈
1.02
Although the absolute difference is negative: -66, the relative decrease change is positive: 1.02. 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:
(47.43 - 6.2)/|47.43| =
41.23/47.43 =
41.23 ÷ 47.43 =
41.23 ÷ 47.43 × 100/100 =
(41.23 × 100 ÷ 47.43)/100 =
(4,123 ÷ 47.43)/100 ≈
86.928104575163/100 =
86.928104575163% ≈
86.93%
(Rounded off to max. 2 decimal places)
The relative percent decrease change
from the original, initial value 47.43 to the final, end value 6.2:
Rounded off to max. 12 decimal places ≈ 86.928104575163%
Rounded off to max. 2 decimal places ≈ 86.93%
The absolute (actual) difference
47.43 - 6.2 = 41.23
By what percentage has 47.43 decreased?
Answer: By ≈ 86.93%
By what percentage is 6.2 smaller than 47.43?
Answer: By ≈ 86.93%
The relative percent decrease change is positive,
so we really have a relative percent decrease
(the value goes down).