Warning signs are popping up along the streets of New York City. CNBC reports:

Manhattan real estate had its worst second quarter since the financial crisis, with prices and sales dropping and inventory rising, according to a new report.

Total sales in Manhattan fell 17 percent in the second quarter from a year ago, according a report from Douglas Elliman and Miller Samuel Real Estate Appraisers and Consultants. The average sales price fell 5 percent to $2.1 million.

Brokers blamed the decline partly on bad weather and other temporary factors. But analysts say the market is facing bigger pressures, from a huge pipeline of new condos to a dwindling number foreigner buyers, volatile stock markets and new tax changes that make New York less attractive.

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