74.
The table shows the production of different types of bikes (in thousands).
The number of years, in which the production of bikes of type C is less than the average production of type A bikes over the years is
Year/Bikes 2015 2016 2017 2018
A 157 194 271 290
B 138 225 146 206
C 255 227 213 239
D 196 304 162 224