Shading area in two way graph for mulitple areas

[Timme Ariens]

Hi,

I am trying to shade multiple areas in my graph. Although i have read multiple forums and also this pdf, i am not able to find a perfect solution for my problem. This is also because i dont know how to efficiently select the time periods as upper and lower bounds.

This is my code:

* Example generated by -dataex-. To install: ssc install dataex
clear
input double(credit_GDP_gap credit_GDP_ratio credit_GDP_ratio_HP) float(time year)
. . 47.1 -49 1959
. . 47.6 -48 1959
. . 47.9 -47 1959
. .   48 -46 1959
. . 48.6 -45 1959
. . 49.2 -44 1959
. . 50.2 -43 1959
. . 51.5 -42 1959
. . 52.9 -41 1959
. . 54.7 -40 1959
. . 55.8 -39 1959
. . 56.1 -38 1959
. . 55.7 -37 1959
. . 54.8 -36 1959
. . 54.1 -35 1959
. . 53.9 -34 1959
. .   54 -33 1959
. . 53.6 -32 1959
. . 54.8 -31 1959
. . 55.6 -30 1959
. . 56.7 -29 1959
. . 56.6 -28 1959
. . 57.1 -27 1959
. . 57.3 -26 1959
. .   58 -25 1959
end
format %tq time

This is my code for the graph:

twoway (line credit_GDP_gap time) (line credit_GDP_ratio time, yaxis(2) lcolor(red) lpattern(dash)), xtitle(year-quarter) title(evolution of credit in the united states)

Now i want to shade for mulitple areas: for example shade between 1980q1 and 1983q1 and 1990q1 and 1983q1. Do i use the rarea option for this and how do i properly set it up? Do i use minimum and maximum and do i use it multiple times or how could i do this efficiently?

Many Thanks in advance!

Timme