"Typically consumers stop buying and businesses stop economic activity in the month or two prior to the election as they wait to see what actually happens and what the result is, and given there was quite a significant change in tax policy between the Labour
Opposition and ourselves it's hardly surprising that some people were waiting to see."
Mr Key said improving confidence was apparent in other areas of the economy.
"It's also true for instance that car dealers have been telling me they've been very busy post the election and were quite quiet for a couple of months prior to it."
Mr Key underscored comments by his Finance Minister Bill English last week that his Government was keeping an eye on Australian moves to establish a register of foreign home buyers.
"If there's a credible register we're not afraid of such a thing, we're just saying we don't think that's the answer to the issues. All a register would give you is arguably a bit better information on what's happening and that might be of merit but realistically for us tackling the housing issue - which we're doing I think very effectively - still sits in that issue of release of land and speeding up the supply of new product."
NZ First Leader Winston Peters said other political parties were now crying "crocodile tears" over the issue of foreign real estate investment, "but when New Zealand First argued for a register of foreign land and house ownership some of their members called New Zealand First xenophobic and racist".
"We ignored that and have long had a bill on the issue of foreign ownership in the parliamentary ballot."
Mr Peters said Chinese and other overseas investors shouldn't be blamed for wanting to buy property in this country, "when we've put the welcome mat out along with flashing neon signs".
"Favourable tax treatment for foreign investment explains why we're now the fifth most preferred market for Chinese investors.
"If New Zealand does not react, this current overseas investment will become an offshore consumer flood."