What are a mnemonic, concept code and geography code? How do they identify Data Buffet time series, singly or in related groups?
Every time series in Data Buffet is identified with a unique alphanumeric key called a mnemonic (pronounced "nuh-mon-ick"). This consists of two parts, separated by a period: a concept code (or "concept") for "what" (the indicator measured), and a geography code (or "geo") for "where" (the place of measurement or similar notion). For instance, "ET.IUSA" (pronounced "E-T dot I-U-S-A") is nonfarm employment (BLS CES report) for the United States. Also:
- XMBAD30.PA = Home mortgages delinquent by 30-59 days - for Pennsylvania
- RHHOLDA.PA001 = Estimated population - for Pennsylvania - Adams County
- NALEGDPUQ.INOR = Gross domestic product - for Norway
Related indicators have concept codes with similar structures, so that a wild card expression in a basket can retrieve them in bulk. For instance, if the dataset is organized by NAICS industry, we embed the official numeric code. For example, this progression:
- RYPEW23Q.IUSA_DMCHI = Wages and salaries for construction (NAICS 23) - for Chicago MSA
- RYPEW236Q.IUSA_DMCHI = For construction of buildings (NAICS 236)
- RYPEW2362Q.IUSA_DMCHI = For construction of non-residential buildings (NAICS 2362)
- RYPEW23?Q.IUSA_DMCHI = Wild card expression: All industry components within construction (23, 231, 2399, etc.)
We define geo codes for countries, subnational areas, and supranational aggregates. Our geo codes are regularized but not necessarily recognizable by name, in part because an area may have very different names under different languages. In some cases, we are able to embed official geographic code numbers within our geo code.
Many (but not all) geo types are distinguishable by wild card. For example:
- LWEMEDPA.IGBR = Median annual income, for the U.K.
- LWEMEDPA.IGBR_SCTL = For Scotland
- LWEMEDPA.IGBR_WALS = For Wales
- LWEMEDPA.IGBR_^^^^ = Wild card expression: All U.K. NUTS 1 areas
Keep in mind:
We design mnemonics to have some regularity but they cannot, in general, be guessed in a vacuum; hence, when first researching and retrieving series, we recommend that you browse the Data Buffet catalog. Once you have collected a basket, provide the mnemonic when you seek support. Given one mnemonic, we can suggest variations and wild card expressions to retrieve related series or to make your basket more concise.
Every mnemonic returns a single series, but a single series may carry multiple mnemonics, including its preferred canonical mnemonic and additional aliases that provide backwards compatibility, brevity, or cross-reference. Aliases are listed in Mnemonic 411.
Ideally, every series sharing a concept code would describe the same measurement, and every comparable measurement would be named with the same concept. Given the scope of our repository and variation between countries, this is only approximately true. To confirm the specific definition of any series, check the metadata we provide.
What is commonly considered the "same" variable may be several distinct series with distinct mnemonics. For instance, there are many alternative house prices indexes published by different agencies. Or, a measurement in a particular survey is reprised in multiple reports, but on different schedules.
What is commonly considered the "same" geographic area may be described with multiple geo codes, because its specifics change over time. The official boundaries of an area may change; it may be static, but is part of a geographic classification that changes. Real estate entities, in particular, have territories that don't align with official definitions but use the same name for familiarity.