How can I add recession bars to a time series plot?

Actually, I want to plot variable x against quarters from 2001Q1 to 2023Q1 and then add shaded recession bars to the plot. In the attached file I also have the U.S. nber recession indicator which is a dummy variable. 1 meaning recession and 0 meaning no recession.

The MATLAB codes I have written are as:

function rescode1;

data = readtable('example_data.xlsx');

qdates = data(:,4);

usrecq = data(:, 2);

x = data(:,3);

figure;

for i= 1:length(usrecq);

if usrecq==1;

recessionplot;

end;

end;

hold on;

plot(qdates,x, '-', 'LineWidth',2);

title('Time series plot of x');

xlabel('Quarters');

ylabel('Y axis');

ax = gca;

ax.XAxis.TickLabels = ({'2001q1','2002q1','2003q1','2004q1','2005q1','2006q1','2007q1','2008q1','2009q1','2010q1','2011q1', '2012q1','2013q1','2014q1','2015q1','2016q1','2017q1','2018q1','2019q1','2020q1','2021q1','2022q1','2023q1'});

xticks([1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89])

Using the above code I cannot generate the recession bars.

Need some suggestions.

Thank you.

Answer 1

[Chunru]

data = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/1488862/example_data.xlsx');
y = data.var3; x=data.quarters; r = data.usrecq;

plot(x, y, '-', 'LineWidth',2)
hold on;

yl = ylim;
xr = x(r>0.5); 
yr = yl(2)*ones(size(xr));
width = 1;
bar(xr, yr, width, 'FaceColor', [0.8 0.8 0.8], 'EdgeColor', 'none', ...
    'BaseValue', yl(1), 'FaceAlpha', 0.3);
%bar(x(r>0.5), y(r>0.5))
ylim(yl)

title('Time series plot of x');
xlabel('Quarters');
ylabel('Y axis');
ax = gca;
ax.XAxis.TickLabels = ({'2001q1','2002q1','2003q1','2004q1','2005q1','2006q1','2007q1','2008q1','2009q1','2010q1','2011q1', '2012q1','2013q1','2014q1','2015q1','2016q1','2017q1','2018q1','2019q1','2020q1','2021q1','2022q1','2023q1'});
xticks([1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89])

[Sabarna Mukherjee]

Thank you for your suggestions. But, what I am wanting is my graph plot to look like is similar to a figure I upload with this comment. Let me know if there are any suggestions on how to accomplish that.

Thank you.

[Chunru]

See the modification above.

[Sabarna Mukherjee]

Thank you so much for your help and suggestions. The code worked!