Finding Annual Amplidute for each of multiple years

I have 12 years of monthly temperature data (144 points). I want to find the annual amplitude, the max value minus the min value each year. This would be easy with only 1 years data but I can;t figure it out with multiple years.

The results should be 12 numbers, 1 amplitude per year.

Thanks in advance for any advice

[KSSV]

When it is easy for 1 year data.....run the same code for each year for 12 times..you will get for each year..

[Andrei Bobrov]

please attach file with your data

Answer 1

[Andrei Bobrov]

diff(reshape(yourdata,2,[]))'