IO Wait is consistently touching high values around 60-70% during load run

I am stuck on an IOwait related problem, the server I am monitoring shows a very high value for IOwait during my load run time **(50%-70%)**. I generated this data using the SAR report command. The ideal value should be below **8%-9%** as the server has **12 cores(1/12 ~ 0.08)**. I read this somewhere and took the assumption accordingly. What can be done to rectify this high IOwait problem, how is it related to other factors in the server which can be checked for to improve the performance.