* Dollar index declines for third straight session
* Weaker U.S. GDP, home sales data pressure greenback
* Aussie, kiwi jump on hopes for Chinese stimulus (Updates market action, changes dateline, previous LONDON)
By Richard Leong
NEW YORK, Dec 22 (Reuters) - The dollar slipped against a basket of currencies on Tuesday as traders booked profit-taking on bullish greenback bets following the Federal Reserve's interest rate increase last week and a steep drop in existing home sales in November.
Commodity-linked currencies including the Australian and New Zealand dollars climbed sharply against the greenback as oil prices stabilized above 11-year lows and investors hoped for more official action to support growth in China.
"There's a lack of clear momentum for the dollar in the past week," said Brian Dangerfield, currency strategist at RBS (L:RBS) Securities in Stamford, Connecticut.
Traders have preferred to book their profits on their bullish dollar positions, which are supported by the Fed's widely expected rate hike and its signal to raise rates further in 2016, rather than building their long dollar bets, analysts said.
The dollar index, which measures the greenback against six currencies, fell 0.35 percent at 98.045 .DXY . It declined three straight sessions and briefly broke below the 50-day moving average at about 98.02.
The greenback fell 0.2 percent to 120.93 yen JPY= after touching its lowest level in a week earlier.
"The trend is still dollar positive as long as the economy performs," Dangerfield said.
U.S. gross domestic product grew at a 2.0 percent annual pace in the third quarter, a tad slower than the 2.1 percent rate reported last month, the Commerce Department said. Economists polled by Reuters had forecast a downgrade to 1.9 percent. urn:newsml:reuters.com:*:nLNNMNEB0Q
There were signs that U.S. economic growth might struggle to gain traction. A private report showed existing home sales plunged 10.5 percent in November, their steepest drop since July 2010. urn:newsml:reuters.com:*:nL1N14B0PB
The euro strengthened again, brushing off the indecisive outcome of the weekend Spanish elections and its possible risk to economic reforms in the euro zone's fourth-biggest economy.
The single currency was up 0.6 percent at $1.0976 EUR= and up 0.3 percent at 132.60 yen EURJPY= .
Among other major currencies, the Aussie and Kiwi dollars both gained more than 0.7 percent to $0.7248 AUD=D4 and $0.6812 NZD=D4 , respectively.
There were hopes of steadier prices for oil and other industrial commodities including iron ore, Australia's largest export, after the government announced a series of reforms at a major meeting of China's Communist leadership, analysts aid. urn:newsml:reuters.com:*:nL3N14A35X
China's yuan CNH= gained marginally against the dollar for a second day with its offshore rates 0.3 percent higher at 6.5281 yuan per dollar CNH= , halting falls that have taken it to its weakest since a devaluation in August.