Missing data plot with 2 categories of information

[jkmusyoka]

I am interested in a missing data plot that has two categories of information - the missing and non-missing data. The currently functionality splits the non-missing information into rain and dry. In my efforts to merge these into one, I have succeeded in giving them the same color in the plot but the legend remains unchanged with the 3 categories. How do I change the legend to reflect this modification? or better how do i get such a plot without modifications?