The following table shows the items of expenditure of a company (in Rs. lakh per annum), from 2015 to 2019.

Year	Salary	Fuel and transport	Bonus	Interest on loans	taxes
2019	250	90	5	23.5	80
2018	350	110	2.5	30	110
2017	325	100	3.5	40	70
2016	300	125	4	35	90
2015	400	140	3	45	100

What is the average amount of interest per year which the company had to pay during this period?