Yield swings for five-year Japanese government bonds shot to record levels Monday, a day before an auction, after Bank of Japan Gov. Haruhiko Kuroda chose to leapfrog across notes and focus new purchases on longer debt.

Ten-day volatility in the yields soared to 434 percent Monday, 11 days after Kuroda announced a doubling of bond buying to get 2 percent inflation in two years.

The yields gyrated from a record low of 0.095 percent last month to 0.32 percent on Thursday as the BOJ unveiled its intention to buy JGBs maturing in as long as 40 years rather than gradually extending the original three-year limit.