How to not include NA values with LINEST function

Hi,

I used this function to calculate the slope from a range with #N/A values and it worked fine:

=SLOPE(IF(ISNA(H5:H33),"",H5:H33),IF(ISNA(G5:G33),"",G5:G33))
(finished with ctrl + shift + enter)

So i assumed this would work to in order to calculate the std error of the slope:

=INDEX(LINEST(IF(ISNA(H5:H33),"",H5:H33),(IF(ISNA(G5:G33),"",G5:G33)),1,1),2,1)
(finished with ctrl + shift + enter)

But I was wrong.

Any ideas of how to get this to work?

Thanks,

Harald