This graph:
https://fred.stlouisfed.org/graph/?g=oidh
Let me reset the computer and start over.
Okay. At FRED. I create a new graph showing Real GDP, and set the units to Percent Change from Year Ago.
Then I add a second line to the graph, showing TCMDO debt. The units come up as Percent Change from Year Ago (matching the previous units setting that I made) and I change them to Billions of Dollars. When the graph changes, the debt numbers are so big that the Percent Change in Real GDP line disappears from view. As expected.
I add a second data series to the second line: nominal GDP in billions. I make the formula read a / b and apply it. Both lines are now visible again.
Using the field that is low on the EDIT LINE 2 form, I change the units to "Percent Change from Year Ago". The graph changes accordingly. Here's what I have on my screen:
(click the image to see an enlargement) |
Okay. I close the EDIT LINE 2 window and click Share Links: Page Short URL to save my settings. This URL comes up:
The graph appears to be unchanged. But the "change the units" field (below the formula field) has gone blank.
https://fred.stlouisfed.org/graph/?g=oidoI bring up that link in a new Firefox tab, click EDIT GRAPH, and select the EDIT LINE 2 window. Here's how my screen looks now:
(ditto) |
Earlier today when I created this graph the first time, I didn't discover the 'blank field' error until several steps later when my graph appeared to be incorrect.
It is possible that this "later" graph was not incorrect (I'm not sure yet), and the blank field error only affects the screen display of the EDIT LINE form. I didn't check this. But I think the problem is more severe, and the blank field error is compounded when the Page Short URL graph is used as the basis for another graph.
Here: I take the oido graph above, the Page Short URL link graph, and change the Graph Type from line to scatter. I make the circle marks smaller and the line width thicker. Here's what I get:
The 'oido' graph as a scatter plot |
Here's the old graph I was trying to duplicate:
http://research.stlouisfed.org/fred2/graph/?g=bLT from 2012 |
The difference between these two graphs is probably my doing, not a result of the blank-field glitch. I dunno. It usually takes me a couple days to see why there's a problem.
Yeah no, even when I change the modified oido to annual frequency, it looks nothing like the graph from 2012.
Now you know everything I know.