Year over year difference

Sai_Krishna_BH — Thu, 30 Apr 2020 10:59:43 GMT

I have three years 2020, 2019, 2018 each has a set of questions with corresponding responses :

2020 -> a has 10

2020-> b has 15

...

similarly,

2019-> a has value 20

2019-> b has value 25

...

2018 -> a has value 30

2018 -> b has value 35 where a,b,... are questions for that year.

Now the ask is to get the difference for value (2020.a) - value (2019. a), value(2020.b) - value(2019.b) and so on for all consecutive years

I don't want to hard code as in 2021 we would need 2021<->2020

topic Year over year difference in App Development