Consider the set $$\mathcal{S}=\{(a,b,c,d,e):0<a<b<c<d<e<100\}$$ where $$a, b, c, d, e$$ are integers. If $$D$$ is the average value of the fourth element of such a tuple in the set, taken over all the elements of $$\mathcal{S}$$, find the largest integer less than or equal to $$D$$.