This mod era dress lists sizes 10-18, which translates to the following bust measurements:
32.5”, 34”, 36”, 38”, 40”

The main dress uses 9 to 13 balls of yarn at 120 yards per ball, corresponding exactly to an additional ball per size. The remaining yardage is 1 ball of yellow for the flower centers and 3-4 balls of white for flower petals and applied crocheted cord as pictured.