Francis is an old pope
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Next month, Pope Francis will mark his 10th year in the papacy. Will he make it to his 15th year? His 20th? He is already 86: the last pope to reach this age was Leo XIII, who died in 1903 at the age of 93.1 In fact, by my count, only 15 of the 264 popes in history remained pope past their 86th birthday, and only four since the year 1500. Francis is in very small company.
I thought I’d visualize this using data scraped from the Wikipedia article “List of popes”. The resulting dataset popes.csv
runs from Peter to Francis and excludes all the antipopes (who I call the nopes) for a total of 267 rows and 264 unique popes. Check this repository for more info.
Here’s a look at a few entries in the dataset:
library(tidyverse) library(knitr) popes <- here("datasets", "popes", "popes.csv") %>% read_csv() popes %>% arrange(-number) %>% head() %>% knitr::kable(digits = 2, align = "c")
number | name_full | name | suffix | canonization | birth | start | end | age_start | age_end | tenure |
---|---|---|---|---|---|---|---|---|---|---|
266 | Francis | Francis | 1 | NA | 1936-12-17 | 2013-03-13 | NA | 76 | NA | NA |
265 | Benedict XVI | Benedict | 16 | NA | 1927-04-16 | 2005-04-19 | 2013-02-28 | 78 | 85 | 7.86 |
264 | John Paul II | John Paul | 2 | Saint | 1920-05-18 | 1978-10-16 | 2005-04-02 | 58 | 84 | 26.46 |
263 | John Paul I | John Paul | 1 | Blessed | 1912-10-17 | 1978-08-26 | 1978-09-28 | 65 | 65 | 0.09 |
262 | Paul VI | Paul | 6 | Saint | 1897-09-26 | 1963-06-21 | 1978-08-06 | 65 | 80 | 15.13 |
261 | John XXIII | John | 23 | Saint | 1881-11-25 | 1958-10-28 | 1963-06-03 | 76 | 81 | 4.60 |
We can use a histogram to get an idea of how rare it is for a pope to continue on past the age of 86.
Code
library(ggplot2) popes %>% ggplot(aes(x = age_end)) + geom_histogram(binwidth = 2, fill = "#1046b1", color = "gray97") + geom_vline(xintercept = 86, linetype = "dashed", linewidth = .25) + # Labels labs( title = "Pope longevity I", subtitle = "Distribution of ages at which papacy ended", caption = "Source: \"List of popes\" Wikipedia article" ) + scale_x_continuous(breaks = c(40, 60, 80, 86, 100)) + theme_minimal(base_family = "karla") + theme( plot.title = element_text(size = 16, face = "bold", hjust = .5), plot.subtitle = element_text(size = 14, hjust = .5, margin = margin(b = 12)), plot.caption = element_text(size = 8, hjust = 0, margin = margin(t = 10)), axis.ticks = element_blank(), axis.title = element_blank(), axis.text.x = element_text( size = c(12, 12, 12, 14, 12), face = c("plain", "plain", "plain", "bold", "plain"), margin = margin(t = 5), vjust = .5 ), axis.text.y = element_text(size = 12, margin = margin(r = 5)), panel.background = element_rect(fill = "gray97", color = NA), panel.grid.major.x = element_blank(), panel.grid.major.y = element_blank(), panel.grid.minor.x = element_blank(), panel.grid.minor.y = element_blank() )
Though Francis is an old pope, his tenure so far of 10 years is less remarkable. Almost a third of all popes lasted for 10 years or more. And getting another decade in will be tough for Francis as he entered the papacy late in life — 76 years old. Of the popes with tenures of 20 years or more, most started before the age of 60, as the chart below shows.
Code
popes %>% filter(tenure >= 20) %>% bind_rows(tibble(name_full = "Francis", tenure = 0)) %>% arrange(tenure) %>% mutate(name_full = factor(name_full, name_full)) %>% ggplot() + geom_segment(aes(x = age_start, xend = age_end, y = name_full, yend = name_full), linewidth = 1, color = "#1046b1" ) + geom_text(aes(x = age_start, y = name_full, label = age_start), family = "karla", size = 8 / .pt, fontface = "bold", color = "#1046b1", nudge_x = -1.25 ) + geom_text(aes(x = age_end, y = name_full, label = age_end), family = "karla", size = 8 / .pt, fontface = "bold", color = "#1046b1", nudge_x = 1.25 ) + geom_segment( x = 76, xend = 86, y = "Francis", yend = "Francis", linewidth = 1, linejoin = "mitre", color = "#ff505b", arrow = arrow(angle = 30, length = unit(0.15, "cm"), type = "closed") ) + geom_text( x = 74.5, y = "Francis", label = "76", family = "karla", size = 9 / .pt, fontface = "bold", color = "#ff505b" ) + # Labels labs( title = "Pope longevity II", subtitle = "Age spans of popes with the longest tenures", caption = "Source: \"List of popes\" Wikipedia article" ) + scale_x_continuous(breaks = seq(30, 90, 10)) + theme_minimal(base_family = "karla") + theme( plot.title = element_text(size = 16, face = "bold", hjust = .5), plot.subtitle = element_text(size = 14, hjust = .5, margin = margin(b = 12)), plot.caption = element_text(size = 8, hjust = 0, margin = margin(t = 10)), axis.ticks = element_blank(), axis.title = element_blank(), axis.text.x = element_text(size = 12, margin = margin(t = 5)), axis.text.y = element_text( size = c(rep(11, 14), 12) %>% rev(), face = c(rep("plain", 13), "bold") %>% rev(), color = c(rep("gray10", 13), "#ff505b") %>% rev(), margin = margin(r = 5) ), panel.background = element_rect(fill = "gray97", color = NA), panel.grid.major.x = element_line(linewidth = .15, color = "gray80"), panel.grid.major.y = element_blank(), panel.grid.minor.x = element_blank(), panel.grid.minor.y = element_blank() )
We can use a bit of survival analysis to estimate the probability of a pope making it to their 20th year, controlled for whether they started relatively young (below 60 years old) or relatively old (60 and above). The Kaplan-Meier estimates are computed using the survival
package and plotted using the ggsurvfit
package.
Code
library(survival) library(ggsurvfit) popes1 <- popes %>% mutate(old = case_when( age_start < 60 ~ 0, age_start >= 60 ~ 1 )) survfit2(with(popes1, Surv(tenure)) ~ old, data = popes1) %>% ggsurvfit(linewidth = .75) + add_confidence_interval() + geom_vline(xintercept = 10, linetype = "dashed", linewidth = .25) + # Labels labs( title = "Pope longevity III", subtitle = "Survival probability of popes by starting age", caption = "Source: \"List of popes\" Wikipedia article" ) + scale_x_continuous(name = "Years of tenure") + scale_y_continuous( name = "Probability of still being pope", labels = scales::percent ) + scale_color_manual( labels = c("Under 60", "60 and above"), values = c("#ffa600", "#1046b1") ) + scale_fill_manual(values = c("#FFD079", "#9BB8F6")) + guides(fill = FALSE) + theme_minimal(base_family = "karla") + theme( plot.title = element_text(size = 16, face = "bold", hjust = .5), plot.subtitle = element_text(size = 14, hjust = .5, margin = margin(b = 12)), plot.caption = element_text(size = 8, hjust = 0, margin = margin(t = 10)), axis.ticks = element_blank(), axis.title.x = element_text(size = 12, margin = margin(t = 5)), axis.title.y = element_text(size = 12, margin = margin(r = 5)), axis.text.x = element_text(size = 11, margin = margin(t = 5)), axis.text.y = element_text(size = 11, margin = margin(r = 5)), legend.position = c(.75, .9), legend.direction = "horizontal", legend.text = element_text(size = 12), panel.background = element_rect(fill = "gray97", color = NA), panel.grid.major.x = element_blank(), panel.grid.major.y = element_blank(), panel.grid.minor.x = element_blank(), panel.grid.minor.y = element_blank() )
Based on these estimates, the young group has a 33.1% probability of reaching their 10th year while the old group has only a 23.9% probability. On the other hand, the young group has a 6.3% probability of reaching their 20th year while the old group has a 2.3% chance. It should be noted though that the estimates for the old group have a high amount of uncertainty, mainly because few old popes make it to their 20th year.
If Francis completes his second decade as pope, he would be 96. The odds are against him, but it wouldn’t be unheard of. Pope Agatho, elected pope in 678 AD at the age of 100, reigned until his death at age 103.
Data
Footnotes
Although Benedict XVI lived to 95, he resigned the papacy when he was 85.↩︎
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