Spreadsheet checks before running Alimony Child Support in Montana

What the checker catches

Running an alimony and/or child support spreadsheet in Montana isn’t just about plugging in numbers—it’s about verifying that the spreadsheet’s structure matches the jurisdiction-aware rules you’re applying. The DocketMath alimony-child-support calculator includes a spreadsheet checker designed to catch common issues that can quietly distort results.

Below are the high-frequency problems the checker looks for before the calculator runs.

Spreadsheet integrity checks (inputs that break math)

• Missing or mislabeled fields (for example, you enter a “custody” value into a “tax” row).
• Non-numeric entries where math is required (for example, using "$1,200/mo" instead of 1200).
• Percent fields entered in the wrong format

  • Example: entering 20 when the spreadsheet expects 0.20.
• Negative values

  • Unless your worksheet is explicitly designed for negatives, negative inputs often indicate a sign/entry error.

Jurisdiction-aware timeline checks (Montana limitations)

One of the most common “looks right but is wrong” problems is timing. For this Montana check, the jurisdiction data uses a general statute of limitations (SOL) period of 3 years for the relevant limitation concept.

• The checker uses Montana Code Annotated § 27-2-102(3) as the source for the 3-year general rule.
• Important: No claim-type-specific sub-rule was identified for this general check. That means the checker does not attempt to determine a different limitation period based on the specific claim category. Instead, it applies the general/default 3-year SOL.

So if your sheet’s timeline indicates activity outside that 3-year window, the checker flags it based on the general rule in § 27-2-102(3).

Consistency checks that affect outcomes

Even when all inputs are present and numeric, inconsistent structure can change outputs:

• Date alignment: if your spreadsheet uses a “support start date” but other dates (like filing/service or another timeline date) fall earlier, timeline-driven sections may compute in an unexpected way.
• Term/frequency mismatches: mixing “month,” “year,” and “weekly” without consistent conversion can create incorrect totals. If the checker detects likely frequency conversion issues, it warns you.
• Multiple-party data conflicts: for example, income entered for one parent but expenses allocated to the other due to column swapping or row shifts.

Quick “fail” signals

If any of the following occur, the spreadsheet checker will typically warn you (or may refuse to run, depending on how the inputs are provided):

• A key date is blank
• A required number field is empty
• The limitation timeline appears stale/outside the 3-year default period
• A frequency conversion looks off (weekly vs monthly)

When to run it

Treat the spreadsheet checker as a pre-flight step. Run it early enough to catch issues before you rely on output figures that may look plausible but are based on incorrect assumptions.

Best times to run it in a Montana workflow:

• Before your first run of the DocketMath alimony-child-support calculator
  This helps catch missing fields and unit errors before they get “baked into” results.
• After every major spreadsheet change
  Examples: updating income figures, changing support start dates, or revising time-sharing/custody inputs.
• When copying data across versions
  If you move rows, paste from another sheet, or regenerate from another source, run the checker immediately to reduce column drift risk.
• When dates are involved
  Because the checker uses the general/default 3-year SOL from Mont. Code Ann. § 27-2-102(3), rerun it whenever your spreadsheet’s relevant timeline dates change.

What the SOL timing check means in practice

If your spreadsheet includes a relevant date range that appears to exceed the 3-year default rule, the checker flags the timeline.

Try the checker

You can test the workflow quickly using the DocketMath tool. Focus on validating the spreadsheet checker step before you review computed support amounts.

1. Open the calculator: **Alimony/Child Support Calculator
2. Choose/enter Montana inputs for your scenario.
3. Provide or upload your spreadsheet values so the checker can validate:

   • numeric formatting
   • date alignment
   • frequency consistency
   • the general 3-year SOL check logic tied to **Mont. Code Ann. § 27-2-102(3)

Input-output behavior (what changes when the checker finds issues)

Use this checklist to predict how problems may surface:

A fast “sanity check” you can do right now

Before running the calculator, scan your sheet for these three items:

• Are all money amounts in the expected frequency (for example, monthly)?
• Do you have exactly one support start date concept populated (avoid competing start dates)?
• Does your spreadsheet’s date window reasonably fall within 3 years (the default rule under Mont. Code Ann. § 27-2-102(3))?

Related reading

• Alimony & Child Support Estimator Guide for Alabama
• Alimony & Child Support Estimator Guide for Arizona
• Alimony & Child Support Estimator Guide for Colorado