Date Formats
System dynamics program with additional features for economics
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#1882 Date Formats
This is probably a duplicate, since this issue has existed for a long time, but it's a useful example. This file imports 3 BIS data sets (Debt and HPI), two with only quarterly data and one with both annual and monthly data (CPI). I chose the format %Y-%m for the monthly data, having already used %Y-Q%Q for the other two series.
Ravel then converted the monthly into Quarterly, with 4 entries for each Quarter and therefore 12 quarters per year.
We need to either support multiple formats for the same time dimension, or to sample the higher frequency data to generate a lower frequency series, but with the correct identification of quarters M03=Q1, M06=Q2, M09=Q3, M12=Q4.
Discussion
Anonymous
RVL and CSV files. I edited the CPI file to remove the yearly data. The ZIP file still contains all the CPI data unedited.
I know I could have started importing the first two files without specifying a date format, and then the 3rd could have imported fine with the DMYT underlying format. But a new user will not know that. Here's the Excel-edited file which should import fine now; we should enable the automatic creation of this in Ravel.
I'm not sure what you mean by "new user". These data files are sufficiently complex, it would take someone who's been around the traps to navigate their complexity.
As it was, I noticed you had the display format for Date set to %Y-Q%Q, which is not appropriate for monthly data. So I changed that to %Y-%b. Then I noticed you had somehow reset all the dates to quarters - not sure how you did that, so I had to reimport the LONG_CPI file, using the blank format. This of course adds an extra handle for "Frequency", so I then set that to "Monthly" to pick up the Monthly series.
Isn't this what you wanted? Is there anything to do here?
Yes there is! See the attached screenshot (model to come in the next comment). This process still results in 12 quarters per year, and the associated "chunky" plots where three potentially different values--from different months--are stacked on top of each other.
We need to map from months to quarters (and all other date transformations) properly. The simplest here would be to impose quarters on the correct months (3=Q1, 6=Q2, 9=Q3, 12=Q4) and drop the other months. That would do at present. At a later stage we could enable a seamless conversion from one time frequency to another.
Not if you set the display format to %Y-%b or %Y-%m. To get that display, you still have the format incorrectly set to %Y-%Q
RVL file.
Something went wrong previously with the attachment. This is what it is supposed to be.