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TORONTO, March 29 (Reuters) - Canada's main stock index notched its biggest gain in more than six weeks on Thursday, led by resource and financial shares, but still suffered its deepest quarterly decline in two-and-a-half years.
* The Toronto Stock Exchange's S&P/TSX composite index ended up 197.35 points, or 1.3 percent, at 15,367.29, its biggest advance since Feb. 12.
* For the quarter, the TSX fell 5.2 percent, its deepest slide since the third quarter of 2015.
* A report showed that Canada's economic growth unexpectedly slowed in January in a clear sign that first-quarter growth is likely to be weaker than the Bank of Canada had predicted.
* The energy group rallied 2.4 percent, led by a 3.2 percent gain for Enbridge Inc.
* U.S. crude oil futures settled 1.1 percent higher at $70.27 a barrel, boosted by higher stock prices on Wall Street and as market participants weighed a rise in U.S. crude inventories and production against continued supply curbs by major producers.
* The materials group, which includes precious and base metals miners and fertilizer companies, also added 2.4 percent.
* Financials, which account for more than one-third of the weight of the TSX, gained 0.9 percent, while industrials rose 1.2 percent as railroad shares climbed.
* The TSX posted 4 new 52-week highs and 6 new lows. Nine of the index's 10 main groups ended higher.
* The largest percentage gainer on the TSX was First Quantum Minerals Ltd, which rose 8.5 percent, while the largest decliner was Prometic Life Sciences Inc , down 29.0 percent.
* The TSX will be closed on Friday for Good Friday. (Reporting by Fergal Smith)