Help with an array

["Joe" <jgbsys@xxxxxxxxxxxxxxxx>]

Need help with an array that will return true value of positive or negative
values of up or down closes within a specified period of times.
For example, if 11 to the last 21 closes are higher the value should return
+1. If 8 of last 21 closes are higher the value should return a value of -5.
Any help would be appreciated.

Joe