Hi,

I have a panel data from 2003-2018. I have taken the average of (Top Marginal Income Tax from 2003-2010 and 2011-2018). and then sorted it by year.

egen mean_MIT_03_10 = mean(MIT) if year>=2003 & year<2011, by (Region_Name)
egen mean_MIT_11_18 = mean(MIT) if year>=2011 & year<2019, by (Region_Name)
sort year

I now want to create a year index from 2003-2010 and 2011-2018. So that I can create the following graph:

Can anyone please help me? If there is any more calcification you need, please let me know. Thank you.