Stocks could tumble 15% or more even with a mild recession, JPMorgan says

• JPMorgan strategists led by Marko Kolanovic say the recent stock rally is "irrational", suggesting the market is downplaying the risk of an economic downturn. 
• Even a mild recession would cause equities to tumble by 15% or more, the analysts said. 
• A US recession is likely this year as elevated interest rates, a credit crunch caused by the banking turmoil, and geopolitical headwinds weigh on the economy, they added.

The stock market is underestimating the risk of an economic slump this year and even a mild recession would cause equities to tumble 15% or more from current levels, according to JPMorgan.