CANADA STOCKS-TSX closes down, posts best week in 17 months

(Adds closing prices and market details)

By Nichola Saminather

July 22 (Reuters) - Canada's main stock index reversed an early rally to close lower on Friday following five straight sessions of gains, as risk appetite once again ebbed following earnings disappointments from some U.S. technology firms.

The Toronto Stock Exchange's S&P/TSX composite index closed down 82 points, or 0.43%, at 18,982.92. It was still up 3.2% for the week, its best since February 2021.

Global equities rallied this week as strong U.S. earnings boosted risk appetite, but that shifted on Friday after Twitter Inc and Snapchat's owner signaled advertisers had pared back spending in response to a darkening economic outlook.

In Canada "it's almost like collateral damage (related) to what's going on in the United States," said Philip Petursson, chief investment strategist at IG Wealth Management.

Despite recent declines, U.S. technology stocks are not cheap, "so any disappointment in the tech world and you'll see sell-offs like this," he said.

Data showed Canadian retail sales rose 2.2% in May from April, on higher sales at gasoline stations, as well as motor vehicle and parts dealers.

The healthcare group, dominated by cannabis stocks, was the biggest decliner with a 4.2% fall, followed by technology, which lost 1.45%, and materials, which fell 1%.

The energy sector fell 1.3%, financials lost 0.2%, and industrials declined 0.15%.

Despite gains in metals including gold and copper , the materials sector, which includes precious and base metals miners and fertilizer companies, lost 1%

The utilities and real estate groups rose the most, each gaining 0.8%. (Reporting by Nichola Saminather in Toronto; Additional reporting by Anisha Sircar and Devik Jain in Bengaluru; Editing by Aditya Soni and Deepa Babington)