Diameter profiled golf club shaft to reduce drag

A golf club comprising:

• a golf club head comprising a strike face and a hosel defining a hosel internal bore;
• a shaft adapter secured within the hosel internal bore;
• a shaft formed from a fiber reinforced polymer and extending along a longitudinal axis between a tip end and a grip end, the shaft including:
• a tip end section abutting the tip end, wherein the tip end section is at least partially secured within the shaft adapter;
• a grip end section abutting the grip end;
• and
• a tapered section interconnecting the tip end section and the grip end section, wherein the tapered section includes an upper portion comprising an upper 60% of the tapered section and a lower portion comprising a lower 60% of the tapered section as measured along the longitudinal axis, the upper portion abutting the grip end section, and the lower portion abutting the tip end section, the tapered section further including:
• a reference portion at least partially located within the upper portion, wherein the outer surface of the reference portion has a frustoconical shape with a near-constant taper rate;
• a narrowed portion at least partially located within the lower portion and between the tip end and the reference portion, wherein an outer surface of the narrowed portion is recessed relative to a reference surface extrapolated from the frustoconical shape toward the tip end;
• a first region with a first taper rate (R1);
• a second region with a second taper rate (R2);
• a third region with a third taper rate (R3);
• wherein the first region is closest to the tip end, the third region is located closest to the grip end, and the second region is positioned between the first region and the third region.