Multi-threading changing results

New to Julia
8

Moving the threading to the outermost loop removes the data races, and also runs twice as fast (on my laptop):

function bar!(S, lev)
    Threads.@threads for ij in axes(S, 3)
        suma = 0.0
        counta = 0
        for i in axes(S, 2)
            for j in axes(S, 1)
                if S[j,i,ij,1] > 0.05 && S[j,i,ij,2] > 0
                    suma += S[j,i,ij,1] / S[j,i,ij,2]
                    counta += 1
                end
            end
        end
        lev[ij] = suma / counta
    end
    return lev
end

Edit: Sorry! Bad typo in original code!!

The speedup of moving the @threads macro call is actually >12x.

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