Quick fact -
The large stations of IR give sheds to WAP 4 and Wap 7/5 or Wcam etc but sheds are in the supplement stations for example-
1)Hyderabad - Lallaguda (LGD)
2)Chennai - Royapuram(RPM)
2)Mumbai...
more... - Kalyan(KYN)
3)New Delhi - Tuglakabad(TKD),Gaziabad(GZB)
You might be thinking that the biggest station is missing.
Howrah - Howrah(HWH) as well as Santragachi (SRC)
This is the only Metro city station that gives sheds itself 91 WAP 4's and 161 in total(HWH+SRC) and as well as few WDM 3A's