It may have been resolved earlier - I haven't checked in awhile. I would also like to give a big smack upside the head to the folks at ECMA that let this slide. But ask today, and it will tell you that it is still in daylight time! Did they not stop to consider that the host environment would probably already have the capability to do this right? However, if using JSON to specify data, the string representation needs to be used. Also, note that minorGridlines are using the second, shorter formats, as the first formats do not fit the space in each instance. The format option accepts an array of string formats, and will use them in order until a format fits the label area.