I have some stock prices as shown below. I want to count the number of occurrences of "-9" for each stock (stk1 - stk5), and delete a stock if the total number of occurrences of "-9" exceeds 15% of the total observations. For example, stk1 has 5 occurrences of "-9", and therefore, I want to delete the entire column from the dataset.

Thank you very much!

DATA ONE; INPUT date acx dyk ojm wuq btr; DATALINES; 1 16.15 19.63 19.55 15.86 12.36 2 10.74 -9.00 13.01 11.62 17.77 3 18.10 11.51 10.95 10.09 15.88 4 17.00 18.80 11.19 15.87 15.56 5 12.38 -9.00 16.14 10.73 12.85 6 -9.00 14.16 -9.00 11.22 16.59 7 12.60 13.54 12.85 -9.00 11.90 8 -9.00 13.17 10.52 14.97 13.55 9 12.75 13.18 14.41 18.20 14.13 10 -9.00 17.35 11.92 18.61 10.02 11 18.49 -9.00 -9.00 16.01 16.41 12 18.40 12.07 19.66 13.66 18.61 13 -9.00 12.39 15.79 18.00 10.07 14 -9.00 19.72 12.83 19.28 15.46 15 16.77 19.11 -9.00 11.47 10.56 16 10.03 -9.00 10.08 15.21 12.65 17 16.18 10.04 14.14 12.86 14.45 18 19.01 14.67 12.67 19.76 12.06 19 18.86 19.03 16.91 12.99 15.85 20 18.02 12.06 14.99 16.02 13.70 ; RUN;