oneThis plural form is used for numbers like: 1
%1$d degree
otherThis plural form is used for numbers like: everything else
%1$d degrees
%1$d degree
%1$d degrees
%1$d grad
%1$d grader
%1$d degree
%1$d degrees
%1$d grad
%1$d grader
%1$d grad
%1$d grader
%1$d degree
%1$d degrees
%1$d - number of degrees (positive or negative).