ANZ Bank was the worst performer, down 2.3 per cent to $32.15, and Westpac Banking Corp fell 2.2 per cent to $34.50.
A2 Milk Co declined 1.8 per cent to $2.22. The shares gained 7 per cent on Wednesday after A2's ASX-listed rival Bellamy's issued a profit warning, but have dropped back since.
Williamson said the market was starting to come under a bit of profit taking pressure today afternoon, particularly for stocks which rallied earlier in the week such as Meridian Energy, which fell 1.5 per cent to $2.67 and Fletcher Building, which dropped 1 per cent to $10.30.
While local news is thin on the ground, stockmarket trading volumes have been lower with many New Zealanders still on holiday. However, the inauguration of US president-elect Donald Trump next week could stir things up, Williamson said.
Vital Healthcare Property Trust was the best performer on the index, up 1.5 per cent to $2.09, while Sky Network Television rose 1.3 per cent to $4.56 and Mercury Energy gained 1.3 per cent to $3.06.
Outside the benchmark index, Hellaby Holdings rose 0.6 per cent to $3.57. Bapcor's takeover offer for Hellaby has now been declared unconditional, with shareholders who have accepted the offer to receive $3.60 per share within the next seven days. Representatives of the two companies met on Thursday to discuss the takeover.
Veritas Investments was unchanged at 20c. The company said it was still working through the process ahead of a deadline to present a plan for its unprofitable Nosh supermarket business to ANZ Bank New Zealand.