Worked example: interest in New Hampshire

Example inputs

Below is a worked example of an interest calculation in New Hampshire using DocketMath’s /tools/interest tool. This walkthrough is designed to show how the numbers flow, what you typically enter, and how the output changes when you adjust inputs.

Assumptions used in this example

Because your scenario doesn’t specify a particular contract instrument or court order, this example uses New Hampshire’s general/default limitations-period framing—not a claim-type-specific rule.

• New Hampshire’s general SOL period for civil actions is 3 years under RSA 508:4.
• No claim-type-specific sub-rule was identified for this example, so we treat RSA 508:4 as the default (the only jurisdiction rule applied here).

Example fact pattern (inputs you might model)

Let’s assume you’re analyzing interest on an amount related to a civil claim, where the “start” date is when interest begins under the facts you’re modeling (for example, an accrual/trigger date tied to the underlying agreement or court order).

You can model the following inputs:

• Principal (amount): $10,000
• Start date (when interest begins): 2023-06-01
• End date (date you’re computing through): 2026-06-01
• Annual interest rate: 6% (entered as 0.06 in a decimal-style tool)

Limitations-period check inputs (optional but useful)

Even though interest math and “time-bar” questions are separate, many people want a quick check against the default SOL period while they model interest.

Because New Hampshire’s general SOL period is 3 years under RSA 508:4, a practical workflow often includes:

• Accrual date (cause of action accrued): 2023-06-01
• Filing date: 2026-05-20

If the filing is before 2026-06-01, it falls within the 3-year window for the default rule.

Example run

We’ll run the interest calculation in DocketMath /tools/interest using the core inputs above.

Step 1: Compute the time interval

• Start date: 2023-06-01
• End date: 2026-06-01

That span is 3 years. In tool-style terms, the time factor is:

• Time (years): 3.000

Step 2: Interest calculation (simple interest model)

This example uses the simple-interest structure that many interest calculators adopt when no compounding is specified:

• Interest = Principal × Rate × Time
• Interest = $10,000 × 0.06 × 3
• Interest = $1,800

Step 3: Total amount due (principal + interest)

• Total = $10,000 + $1,800
• Total = $11,800

Step 4: Tie-in to New Hampshire’s general SOL framing (RSA 508:4)

Under RSA 508:4, the general/default limitations period is 3 years (and this example uses that default because no claim-type-specific rule was identified).

Using the same timeline:

• Accrual date: 2023-06-01
• Filing date: 2026-05-20

That filing is 11 days before the 3-year mark, so the “within SOL” check—under the default rule—would be within the 3-year window.

Compact recap

How the tool output is typically presented

When you use DocketMath /tools/interest, the key outputs commonly include:

• Calculated interest amount
• Total (principal + interest)
• Date span / time basis used for the math (e.g., fractional years or actual days converted to a year basis)
• Sometimes intermediate figures like days or fractional-year conversion

If the tool settings include compounding or different day-count conventions, your result can change—so ensure the date logic matches your facts.

Sensitivity check

To see how sensitive the result is, adjust one variable at a time while holding the others constant. This also shows how the interest total responds when you evaluate the same default 3-year framing under RSA 508:4.

Sensitivity 1: Change the interest rate (keep time = 3.000 years)

Keep dates the same (3.000 years) and vary the rate:

Takeaway: In a simple-interest model, interest changes proportionally with the rate.

Sensitivity 2: Change the end date (keep rate = 6%)

Now keep the annual rate at 6% and change only the end date:

Takeaway: With simple interest, longer time spans increase interest linearly.

Sensitivity 3: “Within SOL” vs “outside SOL” framing (RSA 508:4)

Remember: RSA 508:4 sets the general/default 3-year period. Whether the claim is timely is a separate evaluation step, but people often compare both together.

Try these filing dates (same accrual date: 2023-06-01):

• Filing date 2026-05-20 → within 3 years
• Filing date 2026-06-10 → outside 3 years by 9 days

What changes: The interest math may look similar for a given interest start/end date, but the “within limitations” outcome under the default rule can flip based on that filing date.

What to double-check when results seem “off”

If you compare runs across scenarios, confirm the tool is using the same:

• Principal (amount subject to interest)
• Rate (e.g., 0.06 vs. 6)
• Start/end dates (especially if the interest start trigger differs from accrual)
• Any day-count or compounding settings (if available)

Small date shifts can matter when the tool calculates time using actual days or fractional-year conversions.

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