r - Expand y scale but limit height of y axis line -

my goal make simple column chart in ggplot2 looks following chart (made in excel):

what i'm finding that, example data such (where 1 percentage value close 100%), options plotting data in ggplot2 leave desired. in particular, haven't found way make following 2 simple things happen together:

1) make y-axis line end @ 100%

and

2) make percentage labels on each bar visible

to address issue, i've tried experimenting different arguments scale_y_continuous() haven't found way meet both of goals above @ same time. can see in example plots , code below.

my question is: how expand y scale percentage labels on each data point visible, y-axis line ends @ 100%?

library(dplyr) library(ggplot2) library(scales)   example_df <- data_frame(label = c("a", "b"),                          percent = c(0.5, 0.99))  example_plot <- example_df %>%       ggplot(aes(x = label, y = percent)) +          geom_bar(stat = "identity",                   fill = "dodgerblue4", width = .6) +          geom_text(aes(label = percent(percent)),                    size = 3, vjust = -0.5) +          scale_x_discrete(null, expand = c(0, .5)) +          theme_classic() 

plot desired y-axis line, non-visible label on bar

here happens when set limit on scale_y_continuous() c(0,1):

example_plot +      scale_y_continuous(null, limits = c(0, 1.0), breaks = seq(0, 1, .2),                         labels = function(x) scales::percent(x),                         expand = c(0, 0)) +      labs(title = "y axis line looks perfect, label on bar off") 

plot y-axis line long, visible label on bar

and here happens when set limit on scale_y_continuous() c(0,1.05):

example_plot +      scale_y_continuous(null, limits = c(0, 1.05), breaks = seq(0, 1, .2),                         labels = function(x) scales::percent(x),                         expand = c(0, 0)) +      labs(title = "y axis line long, label on bar visible") 

you remove regular axis line , use geom_segment create new one:

example_df %>%  ggplot(aes(x = label, y = percent)) +   geom_bar(stat = "identity", fill = "dodgerblue4", width = .6) +   geom_text(aes(label = percent(percent)), size = 3, vjust = -0.5) +   scale_x_discrete("", expand = c(0, .5)) +   scale_y_continuous("", breaks = seq(0, 1, .2), labels = percent, limits=c(0,1.05),                       expand=c(0,0)) +   theme_classic() +   theme(axis.line.y=element_blank()) +   geom_segment(x=.5025, xend=0.5025, y=0, yend=1.002) 

to respond comment: when it's outside plot area, 99% label still being drawn, it's "clipped", meaning plot elements outside plot area masked. so, option, still hacky, less hacky original answer, turn off clipping label appears:

library(grid)  p = example_df %>%    ggplot(aes(x = label, y = percent)) +     geom_bar(stat = "identity", fill = "dodgerblue4", width = .6) +     geom_text(aes(label = percent(percent)), size = 3, vjust = -0.5) +     scale_x_discrete("", expand = c(0, .5)) +     scale_y_continuous("", breaks = seq(0, 1, .2), labels = percent, limits=c(0,1),                        expand=c(0,0)) +     theme_classic() +     theme(plot.margin=unit(c(10,0,0,0),'pt'))  # turn off clipping pg <- ggplot_gtable(ggplot_build(p)) pg$layout$clip[pg$layout$name=="panel"] <- "off" grid.draw(pg)