How John Costello's Win Percentage Compares to Similar Players
John Costello posted a career Win Percentage of 64.71, well above the relief pitcher average of 49.61 — a mark that ranked among the best of his era. Across 4 seasons, the Win Percentage arc showed a promising start, with limited data making longer-term conclusions premature. With 4 seasons of data, the Win Percentage arc was above league norms — too limited for reliable trend analysis. Some season-to-season variance runs through the career line, but the career average remained well above league norms across 4 seasons.
John Costello Lifetime Win Percentage
Stats similar to Win Percentage for John Costello
| John Costello
Win Percentage |
|---|
| Career | 64.71 |
| Season Avg. | 64.71 |
| 162 Game Avg. | 64.71 |
| More Info | See More |
John Costello Win Percentage Per Season
John Costello's Win Percentage for each season of his MLB career, plotted against that year's league average. Switch between comparisons — National League, Hall of Fame, RP, North America, or players born in the same country — to see how he stacked up year by year.
John Costello Win Percentage by Team
John Costello's career Win Percentage totals broken down by each team he played for, ordered by when he first joined that team.
John Costello Win Percentage Year-Over-Year Change
A waterfall chart tracking how John Costello's career Win Percentage shifted from season to season. Each bar represents the change added to his career total that year, making peak and decline phases easy to spot.
John Costello Win Percentage Distribution vs. Comparable Players
Each box summarizes John Costello's seasonal Win Percentage alongside a selected comparison group across all seasons he played. The box covers the middle 50% of seasons, the center line is the median, and the whiskers extend to the min and max. A tighter box means more consistency; a higher median means more output. Use the selector to switch comparison groups.
John Costello Win Percentage — Season-by-Season Breakdown
Every season of John Costello's MLB career with Win Percentage alongside league, Hall of Fame, positional, birth region, and country-of-birth averages for that year. Career totals include sum, average, min, max, and median.
Note: A dash (—) means no qualifying players existed in that comparison group for that season. Most commonly this happens for the Hall of Fame group.
