I am running a regression of a continuous variable on a number of independent variables that include two categorical variables (age and income). There are 4 income categories and 9 age categories. This means I need 3+8=11 dummy vars. I understand that SPSS automatically takes one income category and one age category as the reference categories if I use 4 +9 dummies and enter them into the regression using

When I use the syntax

/regression /dependent=VarY /method = enter Var 1....Inc1 Inc2 Inc3 inc4 age1 age2..........age9 .

These are returned in an excluded vars table after the coefficients table?

Now when running this regression for different regions ( too many regions so Im evaluating the regression separately for each region)--i sometimes get 2 age categories in the excluded vars table. Also, for one region , i get no excluded vars table..what to do?