MRIO: Large Scale MRIO

Eric Clower

August 18, 2026 21:17

INTRODUCTION

Great strides have been made to optimize multi-region input-output (MRIO) analysis in IMPLAN, with special attention to MRIO analyses involving Congressional Districts (CDs) and Combined Regions. These region types require more complex queries of trade data.

Prior to the changes, it was not feasible to analyze an MRIO impact with each CD in the country included as its own group. The recent improvements unlock this use case for IMPLAN users who have access to the Large MRIO feature. Much more complicated MRIO analyses can now be performed.

HOW DOES LARGE MRIO WORK?

For users with access to the Large MRIO feature, a determination is made on whether traditional IMPLAN analysis servers can process the project as is. If the project is determined to be a Large MRIO candidate, the system will send the project to a larger, dedicated analysis server for processing.

Next, MRIO in IMPLAN captures the iterative effects of trade between regions. If the amount of trade of a given commodity going from one region to another falls under the set threshold, IMPLAN will not analyze any more iterations from that commodity trade value. This threshold is traditionally set at $100, but is dynamically adjusted upwards by powers-of-ten for Large MRIO runs.

For Large MRIO Projects, the threshold point for MRIO calculations is determined using an index based on the product of :

The number of groups
The largest value of your final demand
Our precision factor (0.00000001)

If this index is less than $10,000, then your impact will continue calculating until the trade value to be passed between regions reaches $100. However, if this index is more than $10,000, then the impact will continue calculating until the trade value to be passed between regions reaches the next power-of-ten value that is larger than the product.

How is the Trade Threshold Calculated?

Determining Index Formula (# of Groups) × (Largest Final Demand Value) × 0.00000001

If Index < $10,000

Threshold = $100

If Index ≥ $10,000

Next Power-of-Ten

Example: An index calculation of $80,000 sets the analysis trade threshold to $100,000.

HOW DO I KNOW IF I NEED A LARGE SCALE MRIO?

A Large MRIO will be used when your impact has at least 100 groups and meets one of the following criteria:

Have 1 group with a sum value of $1 billion or more or
Have a total value across all groups of $100 billion

With the addition of the Large MRIO feature, IMPLAN will dynamically route your analysis to more powerful services. Once an MRIO analysis is deemed large, IMPLAN will automatically check the Large MRIO index to determine the threshold point for MRIO iterations to end. No extra steps are needed on your part.