Model CumulativeInterest

This model tracks the cumulative interest factor for each investment option over time, reflecting the effect of price changes, investments, and inflation events.

Purpose

CumulativeInterest provides a running multiplier for each option, used to adjust the worth of investments and calculate returns. It is essential for accurate valuation and reporting.

Structure

The model is a dictionary mapping option IDs to data points:

Relationships

• Generated by: Calculator
• Uses: OptionWorths2
• Consumed by: OptionWorthHistory, IdealOptionValuations
• Updated by: PRICE_INFO, CONV_INFLATION, CONV_LIQUIDATE, CONV_INVEST, CONV_EXIT

Implementation Notes

• The cumulative interest factor is updated whenever relevant events affect the option’s worth, such as price changes, investments, inflation, or liquidation.
• The factor is multiplicative: each event applies a change to the previous value.

To calculate the interest earned over a specific interval of time, divide the cumulative interest factor at the end of the interval by the factor at the start:

$$ \text{Interest}_{\text{start} \rightarrow \text{end}} = \frac{\text{CumulativeInterest}_{\text{end}}}{\text{CumulativeInterest}_{\text{start}}} $$

This ratio gives the total growth (including compounding) over the interval for the option.