 Notable exceptions occurred during the end of Emperor Shōwa's (Hirohito's) reign when these figures fell.Only 2,775,000 coins were minted in 1987 (year 62) making it the lowest in the series and a key date.Coins made in 1989 (year 64) are popular among collectors as this was Shōwa's last year of reign which lasted only a week, mintage for this coin was also the 2nd lowest.