maybe an error in http://streamingbook.net/fig/2-10 ?

[tangdi]

At http://streamingbook.net/fig/2-10 , why the window sum of [5, 9] with perfect watermark on the left is 10? Shouldn't it be 14?

[andrewkowal]

This is also noted in the errata https://www.oreilly.com/catalog/errataunconfirmed.csp?isbn=0636920073994