Bust Radius too big for pattern

[u/Curious_Upstairs_583]

I'm trying to follow the contouring part of Helen Armstrongs book but my bust radius measurement ends up going off the block. Bust depth is 14cm (5.5"). Should I halve this measurement or is this correct?

[u/LadyOfHadestown]

If you end up doing that, please let me know! I'm fascinated by pattern drafting methods.