How to access fields inside table

I am having issue in accesing table fields.. 

Here is how I have created my table:

 Device_Asso_Table = makeTable("DeviceTable" 0)

 Device_Asso_Table[key]=list(inst~>name inst~>cellName inst~>libName count)

Key is nothing but a cell name.

When I print my table, it looks like below

("RPPOLY" ("R1" "RPPOLY" "csrN40" 0))

 Format is ("key"(inst~>name inst~>cellName inst~>libName count)) 

 Now I want to increment count based on certain conditions. How do I point to the field count?  

Any help will be appreciated.