Last month, some of the sportier Subaru models were proving hard to find, but in June, dealers may have been hard pressed to locate a number of Audi’s niche popular models for customers.

According to Autotrader’s June scarcity report, which lists certified pre-owned and used vehicles in high demand and low supply nationally as well as in specific regions, Audi’s performance-oriented S models and the A5 showed up frequently on this past month’s lists.

Sporty cars have been gaining steam among consumers for the better part of this year, Autotrader analysts pointed out.  

“Since the start of spring, sporty cars generally have been in the highest demand and lowest supply partly because of the season,” said Michelle Krebs, senior analyst at Autotrader. “However, economic factors, notably higher employment, lower gas prices and an improved wealth factor from a healthy stock market and higher housing prices, apparently have made shoppers more comfortable considering a discretionary purchase like a sporty car.”

The CPO version of the Audi S4, the performance sedan based on the A4, was particularly scarce in June.

This model ranked No. 2 on the national scarcity list and No. 1 in the Atlanta, Philadelphia, Dallas-Fort Worth and San Francisco-Oakland-San Jose markets.

The CPO Audi S4 was also No. 2 in Los Angeles, No. 3 in New York and No. 4 in Boston on the regional scarcity lists.

The CPO model of the Audi S5 performance coupe also made a showing on the national scarcity list, coming in at No.7. The CPO model was also hard to find in a variety of market areas: No. 1 in Chicago; No. 3 in San Francisco-Oakland-San Jose; No. 4 in New York; and No. 7 in Los Angeles and Atlanta.

The CPO A5 came in at No. 1 on the Washington D.C. scarcity report, and the Audi A6 made an appearance, as well.

Breaking down the supply and demand situation for many of these Audi models, Krebs explained we have to look at the numbers.

“On the supply side, the S4, S5 and A5 are low-volume models as new cars so the total number of vehicles in operation for these models is small compared with other Audi models and vehicles from large-volume manufacturers,” said Krebs. “They represent an even smaller percentage of Audi’s certified pre-owned and used inventory.”

And supply is definitely lagging demand.

Audi continues to become and even more popular luxury brand, “posting dramatic growth on the new-car side for several years,” said Krebs.

Krebs also explained that one demographic, in particular, may be turning toward the Audi brand.

“In addition, Autotrader studies show Audi is an aspirational brand particularly with millennials, who may be looking at certified pre-owned and used as a way to acquire their dream brand,” Krebs said.

Subaru’s sportier models also peppered the scarcity lists, as well, after dominating many of the slots in May.

For example, the CPO Subaru WRX was the No. 1 scarcest vehicle last month, and the unit came in at No. 7 nationally on the late-model used list.

Other sporty models that remained scarce in June were a number of Porsche models, the Chevrolet Corvette and the Nissan 370z.

Krebs also pointed out one fluctuation that may be a sign fall is approaching.

“Extremely popular on the new-car side, sport utilities, a category that dominated the scarcity lists during the fall and winter months, also showed up more frequently on the June scarcity list — perhaps a harbinger of a change in the season,” Krebs said.

For example, the CPO Toyota 4Runner was the No. 4 most scarce vehicle in Atlanta last month; the used GMC Yukon came in at the No. 9 spot on the used list in Boston; and the CPO Jeep Wrangler notched the No. 3 spot in Dallas Ft-Worth, among others.

Click below for the full June CPO and late-model used scarcity lists, provided by Autotrader.