166: Free Throw Rates

gtUtils
ggbeeswarm
Published

December 29, 2025

Load data

Code 
library(rlang)
library(cbbplotR)

gs <- readr::read_csv("game_stats.csv")


# function to save table 
gt_save_crop <- function(data, file = NULL, bg = "white", whitespace = 50, zoom = 2, expand = 5) {
  tmp <- tempfile(fileext = ".png")
  
  # Wrap the gtsave_extra call in a tryCatch to handle errors
  tryCatch({
    gtExtras::gtsave_extra(data, tmp, zoom = zoom, expand = expand)
  }, error = function(e) {
    # If there's an error, try using regular gt::gtsave instead
    message("gtsave_extra failed, trying gt::gtsave...")
    gt::gtsave(data, tmp, zoom = zoom, expand = expand)
  })
  
  magick::image_read(tmp) |> 
    magick::image_trim() |> 
    magick::image_border(bg, glue::glue('{whitespace}x{whitespace}')) |> 
    magick::image_write(file)
  unlink(tmp)
}

Free throw rate table

Code 
sum_tbl <- gs |> 
  dplyr::filter(
    year > 2021,
    lubridate::month(date) == 11 | (lubridate::month(date) == 12 &
                                      lubridate::day(date) < 29)
  ) |>
  dplyr::mutate(
        fouls = pf + opp_pf
  ) |> 
  dplyr::group_by(team, year) |> 
  dplyr::summarise(
    total_fga = sum(fga),
    total_fta = sum(fta), 
    total_fouls = sum(fouls),
    ftr = total_fta / total_fga * 100
  ) 


sum_tbl |> 
    dplyr::group_by(year) |> 
    dplyr::summarise(
        avg_ftr = mean(ftr)
    )
# A tibble: 5 × 2
   year avg_ftr
  <dbl>   <dbl>
1  2022    29.7
2  2023    31.1
3  2024    33.1
4  2025    33.2
5  2026    35.6
Code 
# make the table 
bball_header <- glue::glue(
  "<div style='display: flex; justify-content: space-between; align-items: center;'>
      <div>
       <img src='https://a.espncdn.com/combiner/i?img=/redesign/assets/img/icons/ESPN-icon-basketball.png'
       style='height: 40px; width: auto; vertical-align: middle;'>
     </div>
     <div style='flex-grow:1; margin-left: 30px; margin-right: 30px'>
       <span style='display: block; font-weight: bold; text-align: center; font-size: 24px;'>Free Throw Rate Changes by Season</span>
       <span style='font-size: 14px; font-weight: normal; display: block; text-align: center;'>Shows the Free Throw Rate percentile for a given value by season.<br>Only games played <em>before</em> December 29 of each season.</span>
     </div>
     <div>
       <img src='https://a.espncdn.com/combiner/i?img=/redesign/assets/img/icons/ESPN-icon-basketball.png'
       style='height: 40px; width: auto; vertical-align: middle;'>
     </div>
   </div>
  <br>"
)


lookup_values <- seq(30, 40, by = 1)

ptile <- sum_tbl |>
  dplyr::group_by(year) |>
  dplyr::summarise(
    stats = list(
      purrr::map_df(lookup_values, ~tibble::tibble(
        target_ftr = .x,
        percentile = stats::ecdf(ftr)(.x)
      ))
    ),
    .groups = "drop"
  ) |>
  tidyr::unnest(stats) |>
  tidyr::pivot_wider(
    names_from = year, 
    values_from = percentile
  ) |>
  dplyr::rename("FTR" = target_ftr)

ftr_tbl <- ptile |> 
  dplyr::arrange(-FTR) |> 
  gt::gt() |> 
  gtUtils::gt_theme_gtutils() |> 
  gtUtils::gt_column_subheaders(
    `FTR` = list(heading = "FTR", subtitle = "FTA/FGA * 100"),
    `2022` = list(heading = "2021-22", subtitle = "358 teams"),
    `2023` = list(heading = "2022-23", subtitle = "363 teams"),
    `2024` = list(heading = "2023-24", subtitle = "362 teams"),
    `2025` = list(heading = "2024-25", subtitle = "364 teams"),
    `2026` = list(heading = "2025-26", subtitle = "365 teams"),
    heading_color = "black",
    subtitle_color = "gray"
  ) |> 
  gt::fmt_number(
    columns = c(FTR),
    decimals = 1
  ) |>
  gt::fmt_percent(
    columns = c(-FTR),
    decimals = 1
  ) |>
  gt::data_color(
    columns = c(-FTR),
    direction = c("column"),
    method = c("numeric"),
    palette = c("#d7191c", "#fdae61", "#ffffbf", "#a6d96a", "#1a9641"),
    domain = c(.15, .999),
    alpha = 0.6,
  ) |> 
  gt::tab_header(title = gt::html(bball_header)) |>
  gt::tab_source_note(
    source_note =
      gt::html(
        "<hr>Data via barttorvik.com | theme via {gtUtils} <br>
        Data only for games played in a given season before December 29<br>
        <hr><b>Table by Chris at Bless your chart</b>"
      )
  ) |>
  gt::tab_options(table.width = gt::px(550)) |>
  gt::tab_style(
    locations = gt::cells_source_notes(),
    style = gt::cell_text(
      font = gt::google_font("Signika Negative"),
      size = gt::px(11.5),
      weight = 250
    )
  ) |> 
  gt::tab_style(
    style = list(
      gt::cell_text(font = gt::google_font("Signika Negative"),
                    size = gt::px(14)
      )
    ),
    locations = gt::cells_body(
      rows = gt::everything(),
      columns = gt::everything()
    )
  ) |> 
  gt::tab_style(
    style = list(gt::cell_borders(
      sides = c("left", "right", "top", "bottom"),
      color = "black",
      weight = gt::px(2)
    )),
    locations = list(
      gt::cells_body(),
      gt::cells_column_labels(),
      gt::cells_row_groups()
    )
  ) |> 
  gtUtils::gt_border_bars_bottom(c("#0d1e2d", "#c1d6e2",
                                   "#f07e1d"))


gt_save_crop(
  ftr_tbl,
  file = "ftr_tbl.png",
  whitespace = 40,
  bg = "#FFFDF5"
)

ftr_tbl
Free Throw Rate Changes by Season Shows the Free Throw Rate percentile for a given value by season.
Only games played before December 29 of each season.

FTR
FTA/FGA * 100
2021-22
358 teams
2022-23
363 teams
2023-24
362 teams
2024-25
364 teams
2025-26
365 teams
40.0 96.9% 92.0% 89.0% 86.8% 77.0%
39.0 95.5% 89.8% 85.1% 83.2% 72.1%
38.0 93.3% 88.2% 81.5% 79.4% 66.3%
37.0 89.9% 85.4% 76.5% 76.6% 60.8%
36.0 86.6% 82.4% 69.3% 71.2% 54.2%
35.0 83.5% 78.5% 64.6% 65.7% 46.8%
34.0 79.1% 71.1% 56.4% 57.7% 40.3%
33.0 71.8% 65.8% 50.6% 50.8% 35.1%
32.0 64.8% 56.7% 44.2% 44.8% 30.1%
31.0 60.1% 52.1% 38.1% 36.3% 24.1%
30.0 54.7% 47.4% 31.8% 31.6% 18.6%
Data via barttorvik.com | theme via {gtUtils}
Data only for games played in a given season before December 29
Table by Chris at Bless your chart

FTR beeswarm

Code 
ftr_plot <- sum_tbl |>
  dplyr::mutate(
    year_label = dplyr::case_match(
      year,
      2022 ~ "2021-22\n29.7\n358 teams",
      2023 ~ "2022-23\n31.1\n363 teams",
      2024 ~ "2023-24\n33.1\n362 teams",
      2025 ~ "2024-25\n33.2\n364 teams",
      2026 ~ "2025-26\n35.6\n365 teams"
    )
  ) |>
  ggplot2::ggplot(ggplot2::aes(x = factor(year_label), y = ftr)) +
  ggplot2::geom_jitter(
    ggplot2::aes(color = factor(year)),
    width = 0.2,
    alpha = 0.5,
    size = 2.5,
    show.legend = FALSE
  ) +
  ggplot2::stat_summary(
    fun = mean,
    geom = "line",
    ggplot2::aes(group = 1),
    color = "#2c3e50",
    linewidth = 1.2
  ) +
  ggplot2::stat_summary(
    fun = mean,
    geom = "point",
    shape = 21,
    fill = "#2c3e50",
    color = "white",
    size = 4,
    stroke = 1.5
  ) +
  ggplot2::scale_color_viridis_d(option = "mako",
                                 begin = 0.3,
                                 end = 0.8) +
  ggplot2::scale_x_discrete(position = "top") +
  ggplot2::scale_y_continuous(breaks = seq(15, 55, 5)) +
  ggplot2::labs(
    title = "Free Throw Rate is Rising",
    subtitle = "Shows how average D-I Free Throw Rates are climbing up. \nData for all games played through December 29 of each season.  \n",
    x = "",
    y = "FT Rate (FTR)",
    caption = "FTR = (FTA / FGA) * 100 | data: barttorvik.com  \nViz by Chris at Bless your chart"
  ) +
  ggthemes::theme_fivethirtyeight() +
  ggplot2::theme(
    # text = ggplot2::element_text(family = "mono"),
    plot.title = ggplot2::element_text(
      color = "black",
      face = "bold",
      size = 16
    ),
    plot.subtitle = ggplot2::element_text(size = 11, lineheight = 1.1),
    axis.text.x.top = ggplot2::element_text(
      face = "bold",
      color = "black",
      size = 10
    ),
    axis.text.y = ggplot2::element_text(
      color = "black",
      size = 10
    ),
    legend.position = "none",
    panel.grid.major.x = ggplot2::element_line(color = "#f0f0f0", linewidth = 0.3)
  )

ggplot2::ggsave("ftr_plot.png",
                ftr_plot,
                w = 6.5,
                h = 7.5,
                dpi = 600,
                type = "cairo")

ftr_plot