OTTAWA -- This year began with the weakest January for residential property sales since 2015, with the number of transactions down four per cent nationally from last year, the Canadian Real Estate Association said Friday.

Just under 23,970 properties were sold through the Multiple Listing Service in January, down from nearly 24,980 a year earlier, the association said in a regular monthly report.

The national average price for all types of residential properties sold in January was $455,000, down 5.5 per cent from the same month in 2018, the biggest year-over-year decline for a month since last May.

Meanwhile the MLS house price index, which adjusts for differing property types, was up a slight 0.8 per cent, the smallest increase since last June.

"Apartment units recorded the largest y-o-y price increase in January (plus 3.3), followed by townhouse/row units (plus 1.5). By comparison, two-storey single-family home prices were little changed (plus 0.1) while one-storey single-family home prices edged down (minus 1.1)," the CREA report said.

In terms of properties on the market, CREA said supply and demand was "balanced" in more than half of all local markets. Nationally, there were 5.3 months of inventory in January, in line with the long-term average.

Douglas Porter, chief economist for the BMO Financial Group, said housing market conditions vary widely depending on the region but he expects 2019 to be broadly stable in 2019.

"While some fret about an overly weak market -- notably the Bank of Canada -- the national numbers instead suggest that conditions are calm and unremarkable," Porter wrote in a commentary about the CREA report.

"While that may lack drama, a lack of drama may be exactly what the doctor ordered for the housing market at this point."

However, Porter also noted that some regions and local markets were weaker than others in January.

In the Greater Vancouver area, the CREA home price index was down about 4.5 per cent year-over-year. In Victoria, the price index was up 4.2 per cent, while it was up 9.3 per cent elsewhere on Vancouver Island.

The index was up 2.7 per cent in the Greater Toronto Area, and up 6.3 per cent for the Greater Montreal area, but down in Regina (minus 3.8 per cent), Saskatoon (-2.0, and Edmonton (-2.9%).

"It's clear that housing market conditions remain weaker in the Prairie region and the Lower Mainland of British Columbia," CREA chief economist Gregory Klump said in a statement.