I tried to look it up in the documentation (all examples I found elsewhere did not work anymore, probably due to an outdated syntax for earlier versions) how to use \"scaleLabel
Scale title configuration is a header if you scroll down in the documentation.
Here is a simple bar chart example, using scaleLabel which is sligtly modified to illustrate a percentage.
https://jsfiddle.net/r71no58a/4/
scales: {
yAxes: [{
ticks: {
min: 0,
max: 100,
callback: function(value) {
return value + "%"
}
},
scaleLabel: {
display: true,
labelString: "Percentage"
}
}]
}