Why is my table displaying 1x1 in workspace but displays actual values in command window?

So I am trying to convert monthly data into quartely and this is my code (below). However, whenever I run the code below, in the output (command window), I get:

months         TB   
Percent
___________    _______

01-Jan-1961      3.04 
01-Feb-1961      3.11 
01-Mar-1961      3.21 
01-Apr-1961      3.28 
01-May-1961      3.14 
... 

which is what I am looking for but in the workspace table, it shows:

Therefore, when I run the retime function, it shows this error:

Error using timetable/retime
All variables in input timetables must be numeric, datetime, or duration when synchronizing using 'mean'.

Error in econ_406_Assignment_1 (line 22)
tt= retime(TBm, 'quarterly', 'mean');

Any help would be appreciated!

%% 2- Converting TB, CPI and CPIX data from monthly to quarterly. 
quarters = datetime([1961,01,01],'Format','yyyy/MM/dd'):calquarters(1):datetime([2022,06,30]);
months = datetime(1961,01,01):calmonths(1):datetime(2022,06,30);
months = months';
a = readtable("B-Table-1010012201-eng.csv", 'Range', 'A12:B750');
TB = a(1:end,2);
TBm = timetable(months,TB)
tt= retime(TBm, 'quarterly', 'mean');

Answer 1

[Steven Lord]

You're creating a timetable whose elements are tables. If you want to change a table into a timetable instead take a look at the table2timetable function.

Answer 2

[dpb]

months = (datetime(1961,01,01):calmonths(1):datetime(2022,06,30)).';
a = table(randn(size(months)));
TB = a(1:end,1);
whos months a TB

The above simulates what your code to the point of creating TB does -- your a variable is a table and, ergo, so is TB.

Somehow you ended up creating a table that is a cell array of tables as the data variable; your code doesn't precisely show doing that but that's what the workspace shows it does contain.

Do something more like

months = (datetime(1961,01,01):calmonths(1):datetime(2022,06,30)).';
a=readmatrix("B-Table-1010012201-eng.csv");
ttTB=timetable(months,a(:,2);                   % create a timetable
ttTBQ=retime(ttTB, 'quarterly', 'mean');

If the above fails, attach your data file so folks have something specific to utilize for testing code...