- 63-for-71 (88.7 percent) on field goals in his career, including a career-long 54-yard kick.
- Made 37-of-39 attempts (94.9 percent), including 8-of-8 from at least 50 yards and 33 extra point attempts for a career-high 144 points in 15 games in 2020. Led the NFL in made field goals and tied for the league lead in points scored.
- Surpassed Matt Bryant (35 in 2016, 2017) for the most made field goals in a single season with 37, and became the first player in franchise history to make at least eight field goals of at least 50 yards without a miss.
- From Week 4-15 of the 2020 season, made 27 consecutive field goals, the longest such streak in a single season in franchise history and the second-longest streak in franchise history overall.
- Played in eight games for the Falcons in 2019, converting 23-of-26 field goal attempts, 15 PATs and totaling 84 points. Koo led the NFL with most points from Week 10-17.
- Went four-for-four (37, 36, 48, 30) on field goals in his debut with the Falcons against the New Orleans Saints in Week 10 of 2019. Named NFC Special Teams Player of the Week for his performance.
- Made all four field goal attempts, including a 37-yarder, 35-yarder, 29-yarder, and a season-long 50-yarder during Week 14 against the Carolina Panthers in 2019. The Georgia Southern alum also recovered Damontae Kazee's fumble at the Carolina 16-yard line, which set up his 29-yard field goal. Named NFC Special Teams Player of the Week for his performance.
- Spent time with the New England Patriots practice squad during October of 2019.
- Signed with the Atlanta Legends of the AAF in January of 2019 where he was 14-for-14 on field goals in eight games.
- Signed by the Los Angeles Chargers as a free agent following the 2017 NFL Draft; converted three of six field-goal attempts and all nine of his extra-point attempts.