How to use the filter function use only the values that are not #N/A from a data set

I've written a simple "\% error" column that calculates the % error of the lookback with respect to the lookforward values. (1c) If it were perfectly true that "last n days" = "next n days", then this column would be all zeros. Below, write a function that calculates the AVERAGE \% error, using ONLY the values that are NOT #N/A. I've alreadv partiallv written the function. vou iust need to complete it where indicated in the formula bar. fx= AVERAGE(FILTER(S4:S1260, your-answer-goes-here)) I've written a simple "\% error" column that calculates the % error of the lookback with respect to the lookforward values. (1c) If it were perfectly true that "last n days" = "next n days", then this column would be all zeros. Below, write a function that calculates the AVERAGE \% error, using ONLY the values that are NOT #N/A. I've alreadv partiallv written the function. vou iust need to complete it where indicated in the formula bar. fx= AVERAGE(FILTER(S4:S1260, your-answer-goes-here))