Ten-year Treasury yields have surged almost 20% over the past month, predictably crimping fixed income exchange traded funds along the way.

On Wednesday, Bloomberg had an illustrative anecdote regarding the recent bond market calamity: “$450 billion has been wiped out across global bond markets over the past few weeks.”

To put $450 billion into context, Apple (NasdaqGM: AAPL) is the only U.S. company with a market value greater than $450 billion. Facebook (NasdaqGM: FB) and Procter & Gamble (NYSE: PG) would have to more than double in size to get $450 billion.

So things are bad for bonds and some bond ETFs, but these are halcyon days for bearish bond funds, such as the Direxion Daily 20-Year Treasury Bear 3X (NYSEArca: TMV). TMV attempts to deliver triple the daily inverse returns of the NYSE Current 20-Year U.S. Treasury Index.

That is not the same index tracked by the iShares 20+ Year Treasury Bond ETF (NYSEArca: TLT), but TMV does an excellent job of delivering triple the inverse returns of TLT. Ten-year yields rising 20% over the past month has sapped TLT to the tune of 9.1% while fostering a 30% gain for TMV. Bond funds with longer durations will exhibit a greater sensitivity to changes in interest rates. [Bearish Bond ETFs Back in Style]

Investors are noticing. On Wednesday, nearly 1.1 million new shares of TMV were created as the ETF climbed 2.4% on volume that was more than double the daily average. TMV entered Wednesday with a May gain of 14.6%, making it the top performer among Direxion’s triple-leveraged bearish ETFs, according to issuer data.