Dynamic Calculations of Variables

[mlogan]

Hello,

I have tuition fees laid out for 4 years (Variables Fee_YR_01-Fee_YR_04) starting current year (Fee_YR_01). Variables Increase_YR_01-Increase_YR_04 in the sample dataset shows the proposed tuition fee increase rate (in percent) based on the previous year. I want to calculate the future tuition based on this proposed tuition increase rate (in the new variables Fee_New_YR_02 - Fee_New_YR_04). I want a dynamic solution for this calculation.  Thank you all.

My data set looks like this:

data have;
	input Fee_YR_01 Fee_YR_02 Fee_YR_03 Fee_YR_04 Increase_YR_01 Increase_YR_02 Increase_YR_03 Increase_YR_04;
datalines;
1000	1050	1100	1150	0	20	20	20
1000	1070	1100	1150	0	20	20	20
3000	3100	3150	3200	0	15	15	15
3000	3200	3200	3300	0	15	15	15
4000	4150	4200	4250	0	15	15	15
4000	4200	4300	4350	0	15	15	15

;
RUN;

This is the output I want:

Fee_New_YR_02	Fee_New_YR_03	Fee_New_YR_04
1200	1260	1320
1200	1284	1320
3450	3565	3622.5
3450	3680	3680
4600	4772.5	4830
4600	4830	4945

Calculations: Fee_New_YR_02=Fee_YR_01 * 1.2 (increased by 20%)

I have shown you a small set of data. But I have 150 variables for tuition fees and 150 variables for the tuition rate increase.  So I need help on how to do it dynamically. 

[andreas_lds]

You will need to three use arrays:

• fees: array fees Fee_YR_01-Fee_YR_04
• incs array Increase_YR_01-Increase_YR_04
• result array Result_YR_01-Result_YR_04

the a simple loop and the job is almost done.

Have a look at the docs of the array statement, to get the details.

EDIT: Forgot to add a hint about improving the data structure, so here it is: the calculation would be easier if your dataset would not have data in the names of variables (YR_01 ...), but a variable holding the value of the year. With that structure the calculation would look like

data want;
  set have;
  new_fee = fee * (1 + Increase / 100);
run;