How to add your own data to IMPLAN

At times, users might want to replace all the data in an IMPLAN model with their own I/O tables. This is most frequently done in places outside the United States where general IMPLAN data is not available. These instructions will help guide you through the process of adding your own I/O data into the IMPLAN Pro software. This will allow you to use IMPLAN Pros inversion utilities and the impact interface with data you provide. This is different from simply changing a production function or some employment or value added element. To do this successfully, you will need to fully understand input-output accounting as well as IMPLANs Access file structures. All information is available in the Analysis Guide section of the manual and the file layout appendix. You will also need to be familiar with MS Access and writing different types of queries such as append and update queries. The IMPLAN databases are Access 2000 compatible so if you are using Office XP, you will need to stay with Access 2000 compatibility. The first step is to create an industry bridge table from your sectoring to the 528 IMPLAN sectors. All IMPLAN sectors must be accounted for. If you have instances of 2 of your sectors bridging to one IMPLAN sector, you will have to use some method for splitting the IMPLAN data you will need to keep (margins, deflators). There are two typical methods of developing an I/O, the industry by commodity basis (BEA method), or the industry by industry method. IMPLAN uses the BEA method. If you do use an industry by commodity basis, and you treat imports as a negative final demand, it will be easier to get your data into IMPLAN Pro structure. If you use an industry by industry basis, there will be some additional work to get a correct multiplier table. IMPLAN also treats negative final demands as commodity sales. Negative final demands can be entered into the SAFinal Demands table, the software will remove them into the SACommodity Sales table. To create an IxI type model assuming that you have a set of accounts that include, the IxI transactions matrix, value added, employment and final demands. To create an IxC type model, you need the IxC transactions (USE), the Make matrix, value added, employment and final demands. If you are going to work with an aggregated model, there is one thing to consider. It will be much easier to get your data into the software if you can aggregate the model first. However, to be able to get a clean conversion, you need to match the IMPLAN sectors exactly. That is, not introduce new sectors that are splits of an IMPLAN sector. If you have splits, it is likely to be easier to work with the unaggregated model first. IMPORTANT!!!!. DO NOT CHANGE THE LAYOUT OF THE TABLES OR THE TABLE NAMES. SAVE YOUR MODEL UNDER A DIFFERENT NAME BEFORE RUNNING!!!!! CREATE BACKUPS AS YOU GO!!! Steps 1. Create a model through the study area, you might use the Larimer county file that comes with the software. 2. Open your model file in Access. 3. Delete the US Absorption table, US Absorption Totals table, and the US Byproducts table. 4. Import into your model those three tables from the ??NAT528.IMS file (?? Stands for the data year of your model). 5. Delete all information in these three tables. 6. Update the US Absorption with your new absorption table. Note the format of the absorption table file. If your transactions matrix is in a matrix form, then you will need to translate the data from a matrix format to a database format. This usually requires writing a program or a macro. 7. Create a byproducts matrix with 1's on the diagonal, and update the US Byproducts table. If you have an IxC type I/O, update the US Byproducts table with that information. 8. Create a new US Absorption totals table from your new US Absorption table (its the sum of the industries). This can be done with an append query 9. Replace the data in the SA tables. This is all the raw data. If your final demand data set does not include commodity sales, then just zero out the table. 10. Delete all data in the SATransfers table. You will not be able to generate SAMs unless you change the SATransfers data into your code scheme. 11. Replace the codes in the Type Codes table and the Industry/Commodity codes table. Note that if your value added elements do not fit IMPLANs, then try to match the labor income with either the employee compensation or the proprietors income and other value added to the other property type income. 12. Change all records of the RPC Methods table Method field to Observed. You can do this with an update query. 13. Delete the Observed RPC table and import that back into the model from the ??NAT528 file. 14. Calculate your RPC from your I/O data. Delete the elements of the Observed RPC table. Enter your new RPC data into the Observed RPC table. (You can copy and paste from a spreadsheet directly into an Access table provided the structure is the same). 15. Restructure the Deflators table and the margins table to fit your new sectoring scheme. (You can do this later if you want). 16. Once you have this done and the study area data changed, you can exit Access and open the file in IMPLAN Pro. It should load and you should be able to run the multipliers. 17. If your imports came in the form of negative final demands, your model should be correct. Go back to Access and check the calculated Regional Absorption table to see that it matches your import ridden transactions table. 18. If your imports are a row vector from as part of the transactions table, you will need to revise the RPCs in the Regional Absorption table. You will want to replace each set of Industry Code RPCs with the RPC from the row vector so all Industry Code RPCs are the same. Once this is done, go back to the model and recalculate the multipliers only.
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