combo box and value's
 

i have a combo box in my spreadsheet..
480-360 =1
360-360 =2
360-180 =3
240-240 =4
180-180 =5
120-120 =6

these are the term's for a mortgage... how would i go about setting it up
when one choose's a certain term that value could then be put within my
formula to figure otu a mortgage payment if that make's any sense...
thanks
trey