Skip to main content

BOS Worksheet #

Jason Hreha· Updated September 5, 2026

Use this worksheet to document a Behavior Opportunity Size estimate before comparing candidate behaviors. Record the population, period, value unit, and source for each input so another person can review the estimate.

Download editable worksheet (CSV)

The CSV opens in a spreadsheet editor. Enter your four numeric inputs in cells B8 through B11. Its formulas calculate the base estimate and two joint sensitivity scenarios. All inputs start empty. Use the BOS Calculator for a browser-based calculation and a downloadable result.

Define the opportunity #

Context Your entry
Candidate behavior, stated as an observable action  
Target population and inclusion criteria  
Period used for the estimate  
Value unit, such as a currency or defined utility unit  
Prepared by and date  

Record the inputs #

Use a consistent period and value unit. Frequency is the feasible number of behaviors per adopter during that period. Adoption probability is the estimated share of addressable users who will adopt during the same period; enter a decimal from 0 to 1. Do not count the same adoption adjustment twice.

Input Value Source and assumptions
Addressable users    
Feasible frequency per user per period    
Net value per behavior    
Probability of adoption, from 0 to 1    

Base BOS = Users × Frequency × Net value × Adoption probability. Enter nonnegative values. Leave an unknown input blank until you can support an estimate; do not use zero to mean unknown.

Compare the scenarios #

For the lower scenario, multiply each input by 0.8. For the upper scenario, multiply each by 1.2 and cap adoption probability at 1. Multiply the four adjusted inputs to obtain each scenario’s BOS. The scenarios change all inputs together, so the BOS range will be wider than 20 percent. They are assumption scenarios, not confidence intervals.

Scenario Users Frequency Net value Adoption probability BOS per period
Lower: all inputs −20%          
Base: entered inputs          
Upper: all inputs +20%, probability capped at 1          

Record the decision #

Review question Notes
Which input is least certain, and what evidence would improve it?  
Does the behavior remain worth testing under the lower scenario?  
What is the next test, who owns it, and when will you review it?  

Attach the completed worksheet and supporting sources to your decision memo. Keep the same period, units, and population rules when comparing alternatives. See the methodology for the broader behavior selection process.