The markets seem to have picked up his basic message that Tuesday's rate increase is unlikely to be the last, given the persistent strength of the economy.
Japanese officials attribute their country's weakening economic performance this year to the persistent strength of the yen.
Home sales and home construction owe their persistent strength to 30-year mortgages at 6 percent interest, unimaginable last fall.
The new forecasts are a result of the persistent strength in consumer spending even as businesses reduced their orders sharply.
One explanation for the economy's persistent strength is the wealth effect - the feeling of many investors that they are richer after years of big rises in stock prices.
For the Fed, the persistent strength of the housing sector is something they will monitor.
The "poetic temperament" in another not gifted with his endurance and persistent strength would have achieved ruin.
The dollar's persistent strength could prompt some even stronger moves by the United States and its economic allies.
One would be to slow the economy if it shows persistent strength and threatens to increase inflationary pressures.
France's position acknowledges the persistent strength of disparate national interests.