sorting table by decades

trying to sort a table with different years of bridges built with other data about them into groups of decades. Coming from being fairly proficient in java and c++ and the matlab documentation simply does not make sense.

I understand I need to create a new table which sums up the data from each respective year into a information on one decade.

T = readtable("bridgedata.xlsx");

decades = varfun((@floor/10)*10,T(:,'YEAR_BUILT'));

[Stephen23]

Duplicate:

https://www.mathworks.com/matlabcentral/answers/1688609-consolidating-table-from-years-to-decades