Three decades of declining interest rates making debt financing more attractive, increased access to private equity dollars, robust mergers plus acquisition activity have all contributed to a continued decline in the number of public companies both in Minnesota and nationally.

Craig Johnson, senior technical research analyst for Minneapolis-based Piper Jaffray, has maintained years of pricing data on public companies across the United States.

He's seen more than a 20 percent drop in qualifying companies since 2000.

"We used to have over 6,000 stocks in our micro group project," he said. "Active and participating right now we have 4,672."

Those "active and participating" stocks Johnson tracks have two clear basic qualifications: higher than a $25 million market cap and trade at more than $2 per share.

And Minnesota is losing public companies faster than the nation as a whole. Because of the decline, the Star Tribune has decided to recast our former Star Tribune 100 to the Star Tribune 50 list of public companies.

In 2000, the Star Tribune 100 list was culled from a universe of 202 companies, and the 100th-largest public company had to have more than $74 million in annual revenue to make the list.

On last year's Star Tribune 100, $74 million in revenue would have been good enough for No. 61 on the list.

"I think having your list at 50 showcases great companies," Johnson said.

Jeff Cotton, managing partner for the Minneapolis office of Deloitte, said Minnesota is still blessed with a diverse mix of companies, and a recent national survey taken by the firm shows they are increasingly confident in a strengthening economic environment here and nationally.

"We still continue to have a very diverse economy with organizations in all segments of the marketplace across more than a dozen industries that fuel our state and regional economies," Cotton said. "We are less vulnerable to economic shocks that come from these corporations relocating than other parts of the country."

The 50 companies on this year's list saw a collective revenue increase of 4.4 percent to $521.9 billion. Total profits increased 12.3 percent to $36.1 billion.

The list is led by the $184.8 billion health care goliath UnitedHealth Group. The Minnetonka-based company alone accounts for 35 percent of the total revenue and 19 percent of total profits.

The results when parsed company by company are mixed; 29 of the 50 companies on the list saw revenue increases and 27 saw profit grow. ANI Pharmaceuticals of Baudette, Minn., had the largest percentage jump at 68.5 percent, boosted by the acquisition of two hypertension drugs to its portfolio of generic and branded pharmaceutical products.

The 30 companies that didn't make the Top 50 had collective revenue of $1.6 billion. While their revenue as a whole grew at a faster clip of 5.3 percent, collectively they lost $83.7 million.

Recasting our list to the top 50 companies makes it more manufacturing centric. Now, 23 of the 50 companies are in the manufacturing sector, and the 30 smallest skew toward medical device and information technology companies. Among those 30 smaller companies, there are some interesting stories that draw attention from some investors.

Beth Lilly is a longtime investment manager who throughout her career has invested in small-cap and micro-cap companies. She recently opened her own boutique firm, Crocus Hill Partners, to invest private dollars in those unloved companies. She says there are good investment options among Minnesota's small- to micro-cap companies that didn't make the Top 50.

One of those she has recently invested in is Minneapolis-based Tactile Medical, which was ranked 56th this year. Tactile Medical makes pneumatic compression devices that provide treatment options for lymphedema and venus ulcers.

"They are going to benefit from treating chronic conditions at home," Lilly said.

Another one she likes is Eden Prairie-based SurModics (ranked 59th) a maker of drug-coated balloon catheters.

"There are really a lot of wonderful companies that size that nobody is paying attention to," Lilly said.

There could be an uptick in IPOs in coming years if one survey holds true. A national survey from Deloitte of middle-market companies, "America's Economic Engine: Breaking the Cycle," showed that more companies are at least thinking of pursuing an IPO. The survey, published in February, indicated companies are still concerned about operational requirements that make going public more difficult but companies are growing more interested.

In 2015, only 15 percent of the companies surveyed said they might pursue an IPO in the next year, in 2016 28 percent of the companies said they might pursue the option.

Patrick Kennedy • 612-673-7926