NEW YORK (TheStreet) -- The eight-month-old Claymore/NYSE Arca Airline ETF (FAA) was the best-performing exchange traded fund in the third quarter as airline companies loaded up planes with passengers over the summer.

The Claymore/NYSE Arca Airline ETF returned 51%, beating the No. 2

Market Vectors Brazil Small-Cap ETF

(BRF) - Get Report

by 6 percentage points. (Leveraged funds were excluded from our review. The top leveraged fund was

Direxion Daily Financial Bull 3X Shares

(FAS) - Get Report

, which rocketed 78%.

Two key metrics for the measurement of airline health are "available seat miles" and "revenue passenger miles." Available seat miles measures capacity by counting the number of seats available times the distance traveled. Revenue passenger miles multiplies paying passengers by the number of miles traveled. This allows the "load factor" percentage to be found by dividing revenue passenger miles by available seat miles.

The U.S. airline industry's load factor climbed to more than 80% in July and August from a low of 70% in January.

AirTran Airways

(AAI)

set a new personal-best September load factor of 77% on an 11% increase in revenue passenger miles compared with 12 months earlier.

Continental Airlines

(CAL) - Get Report

traffic gained 7% over the same period, and its load factor hit 81.5% on restricted seat capacity.

Taken as a group, the airlines held by the Claymore/NYSE Arca Airline ETF are expected by analysts to see a smaller decline in revenue than in the prior quarter. This optimism combined with relatively quiet energy markets led to super-cruising third-quarter return velocities of 189% in

UAL

(UAUA)

, 98% in

AMR

(AMR)

, 63% in

US Airways Group

(LCC)

, 86% in Continental and 55% in

Delta Air Lines

(DAL) - Get Report

.

The Market Vectors Brazil Small-Cap ETF, started just over four months ago, is weighted toward 12% real estate, 10% homebuilders, 6.9% retail, 5.4% commercial services, 5.4% building materials and 5% telecommunications. If Rio wins the contest to host the 2016 Olympics, this fund is well-placed to score gold. Regardless, its fortune is tied to the rising standard of living in Brazil.

The

Rydex S&P Smallcap 600 Pure Value ETF

(RZV) - Get Report

holds down third place, with a gain of 40% for the quarter. Outstanding holdings include third-quarter returns of 265% in

Hutchinson Technology

(HTCH)

, 259% in

EW Scripps

(SSP) - Get Report

and 177% in

Brunswick

(BC) - Get Report

.

To find the best-rated exchange traded funds, check out our

Top Rated ETFs

page.

Kevin Baker became the senior financial analyst for TSC Ratings upon the August 2006 acquisition of Weiss Ratings by TheStreet.com, covering mutual funds. He joined the Weiss Group in 1997 as a banking and brokerage analyst. In 1999, he created the Weiss Group's first ratings to gauge the level of risk in U.S. equities. Baker received a B.S. degree in management from Rensselaer Polytechnic Institute and an M.B.A. with a finance specialization from Nova Southeastern University.