Wooden Fence - Residential

[bigmakattak]

I am doing an engineering look at an existing 7' -6" high wooden yard fence in Oakland Ca. The fence has 4x6 posts with 8 foot spacing. I am not used to wind designs and don't have software available. From some charts the base wind speed looks to be 92 mph and then an allowance for reducing to about 71 mph for the working stress method. From some calculations that I did with the 4x6 in weak axis bending the post seem to be in the vicinity of 1500 psi for bending stress which is quite high for Doug- Fir posts.
I am looking for some assistance on whether my approach looks reasonable and to see if anyone has a quick method/idea of whether this works or not just by your experience with fences. Hoping to not have to cut it down to 7 foot high which does not need engineering study.

Thanks you!

 

[bigmakattak]

Forgot to mention that the fence is solid with no openings.

Thanks