May 17 on Flights

The number of flights taking off from Sunavarbhumi Airport are as follows 0800-0859 14 flights

0900-0959 19 flights

1000-1059 19 flights

1100-1159 16 flightA

On average, how many flights depart from Sunavarbhumi Airport per hour? 

What if the data is  

0800-0859 14 flights

0900-0959 19 flights

1100-1159 19 flights

1200-1259 16 flight

Does the answer change?