Creating Dates with Values

Hi all,

I have columns as below;

Years and months coming from dateset in number format. What i want to do is to create date out of this numbers. 

Dates has to be last dayof the period 

For instance 2018 and 6 should be 30.06.2018 and 2019 and 3 should be 31.03.2019 and so on. 

Thanks in advance