The Global X FTSE Greece 20 ETF (NYSEArca: GREK) is easily Wednesday’s worst-performing non-leveraged exchange traded fund with a loss of 11.2% on volume that is already more than double the daily average as Greek bond yields spiked as fears of a “Grexit,” a Greek departure from the Eurozone, were renewed. That has GREK trading around its lowest levels in three years.

The radical Syriza party emerged victorious in Greek elections last weekend, but for a couple of days, the party was able to assuage skittish investors that Greece was unlikely to leave the Eurozone. However, Syriza’s more recent rhetoric includes teaming with an anti-austerity party and plans to reverse the public spending cuts that were cornerstones of the original Greek debt negotiation with Germany and other strong members of the Eurozone.

Just two years after Greece brought the Eurozone to the brink of a full-fledged crisis and stoked speculation that the common currency scheme was close to meeting its demise, Greece’s fractured political system has onlookers mulling the possibility of a Eurozone without the country. [Greece ETF Prices in EMU Exit]

On Wednesday, yields on Greek 10-year bonds rose modestly to 10.7%. At 10.7%, those bonds now yield about 500 basis points more than they did at the end of July. Five-year Greek bonds yield 13.5%, more than triple the yield for those bonds at the end of July.

Tumbling Greek bonds are weighing on the country’s banks because investors fear a Grexit would prompt a bank run that results in Greek deposits fleeing for safe locales. That is just speculation at this juncture, but the punishment is real.

“Bank stocks were hit particularly hard, with Piraeus Bank S.A. , Eurobank Ergasias SA, National Bank of Greece S.A. and Alpha Bank AE all falling by more than 25%,” according to the Wall Street Journal.