2.1.1576 Part 4 Section, serAx (Series Axis)

a.   The standard does not place any restrictions on the val attribute of the axId element.

Office requires that the val attribute of the axId element match the val attribute of an axId element in the parent chart.

b.   The standard does not state any exceptions that cause the numFmt child element to be ignored.

Office ignores the numFmt child element but will load and save the element.