boxplot fill color for blocking variable

[deleted_user]

The code below produces a boxplot with the grouping variable of year. The grouping variable is displayed at the top of the graph where the fill in odd years in blue and no fill in the even years. How do I change the code so that a grey fill color is used in odd years and keep the no fill (or white) in even years? I tried the cblockvar= option for the block variable legend, but have not been able to change the color.
Thanks

proc boxplot data=precip_boxplot1;
plot precip*Watershed(year)/blockpos=1 blocklabelpos=above cblockvar= vminor=4 boxstyle=skeletal
nohlabel cboxfill=GRAYFF;
label year='Year'
precip='Precipitation (mm/yr)';
run;

[abdullala]

check the options of cbox=(variable) and cboxfill=(variable) from the tech documentations. these will allow you to assign desired color and fill to a variable (years in your situation). you will need to create this color variable in your dataset precip_boxplot1.