ANNAPOLIS, MD—Ventas has a point with its $1.75 billion proposed acquisition of Ardent Health Services: diversification within the health care real estate sector is a good thing as fundamentals for the various product types ebb and flow depending on the market cycle. (Also, as an aside, hospitals have been an under invested asset class for several reasons, but that is another story).

New data from the National Investment Center for Seniors Housing & Care bolster that first point. It reports that the average occupancy rate for seniors housing properties in the first quarter of 2015 dropped by 0.2 percentage points to 90.2%, from the prior quarter.

On the whole, though, this particular asset class appears solid: As of the first quarter of 2015, occupancy was 3.3 percentage points above its cyclical low of 86.9% during the first quarter of 2010.

NIC also reported that majority independent living properties continued to post stable occupancy levels at 91.2%, the same as in the fourth quarter of 2014, which was the best showing since late 2007 and 1.0 percentage points above year-earlier levels Also, rent growth accelerated to 2.7%, the fastest rate since late 2009.

These properties have benefited from relatively moderate levels of new units being delivered into the market, according to Chuck Harry, NIC's managing director and director of Research, says in a prepared statement. And as the uptick in rental rates show, "strong occupancy levels have started to put upward pressure on rent growth," he adds.

However, the numbers also showed weak absorption in the space. Namely, despite the stable occupancy level, occupancy rates for majority assisted living properties slipped to 88.7% in the first quarter of 2015, down 60 basis points from 89.3% in the fourth quarter and 20 basis points from 88.9% in the first quarter of 2014.

"The absorption numbers were a surprise juxtaposed to generally favorable economic trends and were a contrast to recent trends where absorption had been very strong," Beth Burnham Mace, NIC's chief economist, says in a prepared statement.

"The first quarter numbers are difficult to fully explain", she added "and may be an aberration. We look forward to seeing the second quarter figures to see the extent to which first quarter numbers were related to seasonal patterns or the effects of the flu season on residents. The sector's first quarter numbers are often relatively weak."

In other areas the sector showed similar patterns of growth.

For the broader seniors housing sector, rate of seniors housing's annual asking rent growth increased to 2.4% during the first quarter of 2015, an increase of 0.1 percentage points from the prior quarter and 0.6 percentage points above its year-earlier pace.

Seniors housing annual absorption decelerated to 2.4% as of the first quarter of 2015, compared to 2.7% during the fourth quarter of 2014 and 2.3% during the first quarter of 2014.

The nursing care occupancy rate increased 0.2 percentage points to 88.5% during the first quarter of 2015.

Nursing care annual inventory growth was -0.3% in the first quarter of 2015, while annual absorption was -0.2%. Private pay rents for the sector grew 2.5% year-over-year this quarter, which is 0.2 percentage points below the pace of the prior quarter.