> head(test)
    age popperc
1   0-5       7
2  5-15      14
3 15-20       7
4 20-25       7
5 25-35       7
6 25-30       7
> summary(test)
     age               popperc      
 Length:12          Min.   : 6.000  
 Class :character   1st Qu.: 7.000  
 Mode  :character   Median : 7.000  
                    Mean   : 8.917  
                    3rd Qu.:11.000  
                    Max.   :15.000