The market finally had a good performance on Wednesday after a three-session losing streak. Parker Drilling ( PKD - Snapshot Report ) was able to take advantage of the runup by gaining 10.3%.

The double-digit advance pushed this provider of contract drilling solutions and rental tools to the top of the Zacks #1 Rank List today.

PKD has watched most covering analysts raise their estimates over the past month, thanks to a solid second-quarter report from early August.

The Zacks Consensus Estimate for 2011 has moved higher by approximately 24% in that time to 46 cents per share.

As for next year, the Zacks Consensus Estimate of 71 cents is up more than 12.5% from 63 cents, and marks the potential for year-over-year profit growth of more than 54%.

Both periods experienced 3 upward revisions out of 5 total estimates in the past 30 days.

The second quarter that started this appreciation included earnings per share of 14 cents, which beat the Zacks Consensus Estimate of 8 cents by 75%. This marked the first time in almost 2 years that the company surpassed expectations.

Revenue climbed to $172.8 million from $156.5 million, thanks in large part to strong growth in its Rental Tools segment.

PROS Holdings, Inc. ( PRO - Snapshot Report ) found its way back to the upper echelon of the Zacks #1 Rank Top Performers List on Wednesday. This management software solutions company advanced 8.5%.

PRO was also featured in this article on Aug 24.

Earnings estimates have stood still over the past 30 days, but remain well above levels from 2 months ago.

The Zacks Consensus Estimate for 2011 is 16 cents, or 23% higher than 60 days ago, while the Zacks Consensus Estimate for 2012 has increased 20% in that time to 24 cents.

In addition, current expectations suggest that next year could improve upon this year by as much as 50%.

PRO's second quarter saw earnings per share of 5 cents beat our estimate by 25% and also reverse a year-ago loss. Total revenue soared 33% to $23.8 million.

During the quarter, PRO signed several new customers, re-signed a number of existing customers and released the latest version of its PROS Pricing Solutions Suite. It also established a new reseller in Asia.

Rounding out the top 3 on Wednesday is Town Sports International ( CLUB - Snapshot Report ) , which has an appropriate ticker since it is a leading fitness club company.

Today, it was near the apex of the Zacks #1 Rank Top Performers List with a gain just over 8%.

Earnings estimates have been steadily advancing ever since its solid second-quarter results from late July, which included a raised outlook for the rest of the year.

The Zacks Consensus Estimate for 2011 is 41 cents per share, marking advances of more than 57% in 2 months and almost 8% in 30 days.

The Zacks Consensus Estimate for 2012 is up 56% in 2 months to 64 cents per share, including a push higher by 6.7% in the past 30 days.

CLUB's solid second-quarter had earnings per share of 16 cents surpass the Zacks Consensus Estimate by about 45%. Revenue advanced only slightly to $118 million.

However, same-club revenue was up 1.5%, while total member count advanced 7,000 to 517,000.