M2 or CPI: what does “the value of HKD” actually mean?
Compare money-supply share and consumer purchasing power, with a worked example and a checklist for reading HKD calculations.
Which question does each measure answer?
If you want to compare the cost of a defined basket of goods and services, CPI is the closer reference. If you want to preserve an amount’s mathematical share of a monetary aggregate, an M2 ratio answers that question. Neither is a complete description of your household finances. Your spending mix can differ from the index basket, and money-supply definitions differ between countries.
Federal Reserve · H.6: M1 / M2 · BLS · CPI questions and answers
How does the calculation work?
Take a hypothetical starting amount of 1,000 HKD. Suppose CPI rises from 100 to 120 while an M2 series rises from 100 to 150 in the same period. Multiplying the amount by each ending-to-starting ratio gives 1,200 HKD under CPI and 1,500 HKD under M2. These are teaching assumptions, not observations for this currency. The different answers reflect different benchmarks; they do not show an error.
| Definition | Formula | HKD |
|---|---|---|
| CPI | 1000 × 120 / 100 | 1200 |
| M2 | 1000 × 150 / 100 | 1500 |
What should you check for HKD?
Check the starting month, ending month, source unit and series definition before interpreting a result. A monthly average and an end-of-period stock are not interchangeable. Use the same series on both sides of a ratio and keep its seasonal-adjustment treatment consistent. Missing observations are not zero, and a demo series is not evidence of actual monetary growth.
HKD · Data & methodology
Local M2: Official data
Latest observation: 2026-06
Unit: HKD million
How can you use the result without overstating it?
Start with the past-money calculator and choose a period with available observations. Read the source notes before comparing the results. For net-wealth comparisons, remember that deposits, withdrawals and saving can change wealth as well as investment performance. An M2-adjusted comparison does not establish how much money flowed into asset markets or what return you should expect.
Questions & answers
Is M2 growth my personal inflation rate?
No. M2 describes a monetary aggregate. CPI describes a basket of consumer prices, which also differs from an individual household’s spending.
Why do two calculations give different amounts?
They scale your starting amount by different ratios. Use consistent months and definitions, then interpret each answer according to what it measures.