MATLAB: How to scale values in y-axis to be 1-100%

Question

The code below is what I have tried to do. I want to scale the value 200 to become 100% in the plot and the value 100 to become 50%. The x and y values are just made up, I actually need to plot 1440 different values. Help needed! Thanks in advance!

clear
x = [1, 2, 3, 4, 5, 6, 7, 8, 9];
y = [5, 50, 200, 180, 100, 60, 53, 0, 2];
figure
ax = axes;
plot(x,y); 
set(ax, 'YTick', [0:10:100], 'YLim', [0, max(y)]);
ytickformat(ax, 'percentage');
ax.YGrid = 'on';
xlabel('Time (Minutes)');
ylabel('Energy Percentage');

Answer 1

clear
x = [1, 2, 3, 4, 5, 6, 7, 8, 9];
y = [5, 50, 200, 180, 100, 60, 53, 0, 2];
figure
ax = axes;
plot(x,y); 
set(ax, 'YTick', [0:10:100], 'YLim', [0, max(y)]);
ytickformat(ax, 'percentage');

Save the yticklabels to a variable as it might be difficult for you to create them

ylbs = ax.YTickLabel;

Set yticks to 0:20:200

ax.YTick = 0:20:200;

and label them from 0 to 100

ax.YTickLabel = ylbs;
ax.YGrid = 'on';
xlabel('Time (Minutes)');
ylabel('Energy Percentage');

Or other way of generating tick label by yourself is

generate number from 0 to 100, convert it to string, split it to cell and add a percentage sign using strcat,

clear
x = [1, 2, 3, 4, 5, 6, 7, 8, 9];
y = [5, 50, 200, 180, 100, 60, 53, 0, 2];
figure
ax = axes;
plot(x,y); 
set(ax, 'YTick', 0:20:200,...
    'YTickLabel',strcat(split(num2str(0:10:100)),'%'),...
    'YLim', [0, max(y)]);
ax.YGrid = 'on';
xlabel('Time (Minutes)');
ylabel('Energy Percentage');