* MSCI ex-Japan up 33 pct in 2017, best showing since 2009
* MSCI world equity index near record highs, up 21.5 pct YTD
* Bitcoin slip more than 10 pct to under $14,000
* Copper, gold strength props commodity currencies higher
* Dollar slips as U.S. Treasury yields come off recent highs
By Swati Pandey
SYDNEY, Dec 28 (Reuters) - Asian shares marched towards a decade high on Thursday, on track for their best annual performance since 2009 as investors bet on a bright outlook for the global economy with copper at a four-year peak.
MSCI's broadest index of Asia-Pacific shares outside Japan advanced 0.8 percent to stay within sight of November's high of 570.2 points, a level unseen since late 2007.
It has risen about 33 percent in 2017 thanks to improving global growth as exports boomed, sharply lifting corporate earnings. Much of the positive impulse is expected to extend into 2018.
On the day, most Asian markets joined the year-end party with South Korea's KOSPI and China's CSI 300 index both up about 1 percent, and Hong Kong's Hang Seng index adding 0.7 percent. Jakarta's SE Composite Index advanced to a record peak.
Japan's Nikkei and Thailand's SET Index were the only two Asian markets in the red.
MSCI world equity index, which tracks shares in 47 countries, also held near record highs. It has surged 21.5 percent this year.
Trade was light across the board with many market participants on holiday.
In the cryptocurrency arena, bitcoin's woes persisted as it fell more than 10 percent to under $14,000. The losses came as South Korea said it will impose additional measures to regulate speculation in cryptocurrency trading.
The world's biggest and best known digital currency has skyrocketed more than 14 times on the Luxembourg-based Bitstamp Exchange this year. And, even after a crushing blow from almost $20,000 it is still up about 39 percent in December alone.
Elsewhere, currencies of commodity exporting countries got a boost from stronger metal and oil prices.
Copper rose for a tenth straight session to a fresh four-year high.
Prices of the metal, considered a barometer for global growth and used widely in power and construction, are up 31 percent in 2017.
Gold climbed to a one-month top while oil was not far from this week's 2-1/2 year peak.
All that pushed the commodity-driven currencies of Australia , New Zealand and Canada to multi-week highs.
The greenback slipped against the yen while the dollar index sagged to near one-month lows as U.S. Treasury yields came off recent highs.
Treasury 2/10s yield curve slipped below 52 basis points, from almost 64 basis points last week.
"The dollar bears are getting their last licks in for 2017, perhaps foreshadowing of things to come in 2018," said Stephen Innes, head of Asia-Pacific trading at OANDA.
The dollar index, which measures the greenback against other major currencies, is seen ending more than 9 percent lower in 2017 as the reflation trade seen at the start of the year faded.
For the year, the dollar is down more than 3 percent on the yen.
In commodities, spot gold rose 0.4 percent to $1,292.2 an ounce, a level last seen in late November.
Brent crude, the international benchmark for oil prices, rose 16 cents to $66.60 a barrel. U.S. crude added 15 cents to $59.79 after climbing to a 2-1/2 year high of $60.01 on Tuesday.
Editing by Richard Borsuk and Shri Navratnam