S Corp. has 200 shares of outstanding stock (voting common stock only), which are owned by three unrelated individuals as follows: Alex owns 120 shares, Bob owns 60 shares, and Chris owns 20 shares. During the year, S redeemed a portion of Alex's shares for $20,000. Disregarding United States v. Davis, for the redemption to qualify for sale treatment, the lowest number of shares that S must redeem must exceed how many?