@Reeza    I am having trouble to calculate how many people each month took insurance?   Below is the data for first 22 days in january. Remaining data is same as below for every month :-   date   no_of_births 1/1    1482 1/2    1213 1/3    1220 1/4    1319 1/5    1262 1/6    1271 1/7    1355 1/8    1219 1/9    1253 1/10  1339 1/11  1293 1/12  1295 1/13  1296 1/14  1333 1/15  1409 1/16  1330 1/17  1286 1/18  1268 1/19  1336 1/20  1422 1/21  1318 1/22  1302     ... View more