CF Industries (CF) and KongZhong (KONG)

Well that wasn't a very good way to start off the week.

In Monday's session, the Dow, S&P and NASDAQ each declined by more than 1%. However, a number of Zacks #1 Rank stocks were able to finish in the green, and two in particular gained by more than 6%.

A brokerage upgrade was enough to keep CF Industries Holdings, Inc. ( CF - Analyst Report ) above water on an otherwise difficult day in the market. But the fertilizer giant didn't just survive; it became the top-performing Zacks #1 Rank on Monday.

CF gained 6.25% today, which would have been a respectable performance in a more hospitable environment, but was downright exemplary on a day when the Dow regressed in the triple digits. Volume eclipsed 4.2 million shares, compared to the daily average of nearly 2 million.

CF is a great example of a Zacks #1 Rank stock. Earnings estimates for the company have been trending higher for months now; not just a blip here or there but a steady improvement in analyst expectations. The Zacks Consensus Estimate for 2011 is currently $15.56 per share, marking a gain of 8.3% in the past 30 days. In this time, twelve out of 15 total estimates were revised higher, marking a very impressive agreement among analysts.

Furthermore, the Zacks Consensus Estimate for this year is also up 13.5% in 2 months. There has even been an advance of 13 cents in the past 7 days, which is just a bit under 1%.

The Zacks Consensus Estimate for 2012 is $13.81 per share, up 11% in a month and 14.6% in 60 days. Again, there is nice agreement among analysts as 10 estimates out of 13 total moved higher in the past 30 days. This period has also seen some improvement in the past 7 days.

In its first-quarter report from early this month, the company earned $3.81 per share, which beat the Zacks Consensus Estimate by nearly 18%. Net sales surged 134% to $1.2 billion from $502.4 million a year earlier, thanks to the inclusion of Terra.

The company sees a very positive environment for North American plant nutrient producers, given the strong spring demand, tight global grain stocks and favorable natural gas prices.

CF Industries Holdings, Inc. is the holding company for the operations of CF Industries, Inc., which is a global leader in manufacturing and distribution of nitrogen and phosphate products. It serves both agricultural and industrial customers.

CF is the only company from the Fertilizers industry on today's Zacks #1 Rank List.

KongZhong Corporation ( KONG - Snapshot Report ) was able to fight the negative tide on Monday as it prepares to announce its first-quarter results tomorrow. Shares advanced 6.06% today with volume moving past 1 million shares, which is practically double the daily average of around 513,000.

KONG is one of the leading providers of digital entertainment services for consumers in the People's Republic of China. Its three main business units are Wireless Value Added Services (WVAS), mobile games and Internet games.

It is one of three companies from the Internet Content industry on today's Zacks #1 Rank List. The other two names are China Distance Education Holdings Ltd. ( DL - Snapshot Report ) and LookSmart, Ltd. ( LOOK ) . (By the way, LOOK was also a top-performing Zacks #1 Rank on Monday. It gained 4.36%, which put it right behind KONG).

There's good reason to be excited about KongZhong's upcoming numbers. The company last reported quarterly results in early March, and earnings estimates took a sharp upturn in response. Plus, KONG has put together 8 straight quarters with better-than-expected profit.

The Zacks Consensus Estimate for 2011 is currently 48 cents per share, which is up 2.1% in 2 months and more than 41% in 3 months. For 2012, the Zacks Consensus Estimate of 63 cents has advanced 5% in 2 months and more than 21% in 3 months.

Analysts currently expect 2012 profit to advance more than 31% from 2011.

The fourth-quarter report, which sparked this upward movement, saw earnings per share of 15 cents, which soared past the Zacks Consensus Estimate by 87.5%. Revenue increased by 5% to $36 million. The company attributed the performance to diversification into Internet games, cost efficiencies and a stabilizing WVAS market.

KONG expects total revenues for the first quarter between $38.5 million and $39.5 million, as well as non-GAAP profit of $6 million to $7 million.

At the moment, the Zacks Consensus Estimate for the first quarter is 7 cents per share, which is unchanged in the past 3 months.