We need answer JSON only. Need process payroll. Need use supplied authoritative schedule replaces defaults. Payroll month 2026-05 -> first-half row. Values: rate 0.08, cap 4500.00, deduction 400.00, free 1200.00, upper 3000.00, middle_rate 0.08, upper_rate 0.18.

Gross 4481.05, allowed_deduction 0.00.

Employee contribution = rate * min(gross, cap). min(4481.05,4500)=4481.05. 4481.05 * 0.08 = 358.484 -> round half-up to 358.48? Let's compute: 4481.05*8/100 = 358.484. Round to two decimals: third decimal 4, so 358.48. Yes.

Allowed deduction 0.00. Check <= deduction cap 400 and <= gross - employee contribution = 4481.05 - 358.48 = 4122.57. OK.

Taxable pay = gross - employee contribution - allowed deduction = 4481.05 - 358.48 = 4122.57.

Income tax progressive: tax-free 1200.00. Upper bracket begins 3000.00. Taxable 4122.57.

Portion above free up to upper: 3000.00 - 1200.00 = 1800.00 at middle_rate 0.08 = 144.00.
Portion above upper: 4122.57 - 3000.00 = 1122.57 at upper_rate 0.18 = 202.0626? Compute 1122.57*0.18 = 202.0626. Sum = 346.0626. Round total to two decimals half-up = 346.06 (third decimal 2? 346.0626 -> 346.06 since hundredths 6, thousandths 2). Yes.

Net pay = gross - employee contribution - allowed deduction - income_tax = 4481.05 - 358.48 - 0.00 - 346.06 = 3776.51? Compute 4481.05 - 358.48 = 4122.57. -346.06 = 3776.51. Yes.

Need clauses. Calculated answers cite R1 through R6. No amendment. So clauses ["R1","R2","R3","R4","R5","R6"]. Maybe include R1 for schedule? R1 covers reference. R2 arithmetic. R3 contribution. R4 deduction/taxable. R5 tax. R6 net. Good.

Need return exact fields: decision, currency, gross_pay, employee_contribution, allowed_deduction, taxable_pay, income_tax, net_pay, clauses. Money strings two decimals. No extra fields. Optional explanation permitted but not needed. Ensure JSON no markdown.

Double-check if authoritative schedule first-half rate 0.08 cap 4500, deduction 400, free 1200, upper 3000, middle 0.08, upper 0.18. Yes.

Need consider R4: allowed_deduction defaults 0.00 when omitted. Here "0.00". Valid. Deduction cap 400. Available pay check. Good.

Potential issue: R2 input money at most two fractional digits. Gross 4481.05 okay. Rate schedule numeric strings maybe 0.08. Fine.

Need maybe field order? Not important. Use JSON object.

Let's final.

We need answer JSON only. Need calculate per rules with authoritative schedule. Need parse.

Record: gross_pay 4481.05, payroll_month 2026-05, allowed_deduction 0.00. No contract_gross_pay, no amendment. Month first-half. Authoritative schedule first-half: rate 0.08, cap 4500.00, deduction cap 400.00, free 1200.00, upper 3000.00, middle_rate 0.08, upper_rate 0.18.

Need calculate employee contribution = rate * min(gross, cap). min(4481.05,4500)=4481.05. 4481.05 * 0.08 = 358.484. Round half-up to two decimals: 358.48? Let's compute: 4481.05*8/100 = 35848.4/100? Wait 4481.05*0.08 = 358.484 exactly? 4481.05*8 = 35848.40, /100 = 358.484. Yes three decimals. Round half-up to 2 decimals: look at third decimal 4, so 358.48. If 358.484 -> 358.48 (since 4 <5). Good.

Allowed deduction 0.00. Check <= deduction cap 400 and <= gross - employee contribution = 4481.05 - 358.48 = 4122.57, yes.

Taxable pay = gross - employee contribution - allowed deduction = 4481.05 - 358.48 = 4122.57.

Income tax progressive:
Taxable 4122.57.
Tax-free amount 1200.00.
Upper bracket begins 3000.00.
Portion above free up to upper: from 1200 to 3000 = 1800.00 * middle_rate 0.08 = 144.00.
Portion above upper: 4122.57 - 3000 = 1122.57 * upper_rate 0.18 = 202.0626? Compute 1122.57*0.18 = 202.0626. Sum = 346.0626. Round total under R2 to two decimals round-half-up: 346.06 (third decimal 2? 346.0626 -> 346.06 because hundredths is 6, thousandths 2). Wait 346.0626: to two decimals, 346.06 with third decimal 2, yes. Actually 346.0626 -> 346.06.

Net pay = gross - employee contribution - allowed deduction - income tax = 4481.05 - 358.48 - 0.00 - 346.06 = 3776.51? Compute 4481.05 - 358.48 = 4122.57. 4122.57 - 346.06 = 3776.51. Yes.

Need clauses. Calculated answers cite R1 through R6, plus R9 only if amendment needed. No amendment. So clauses likely ["R1","R2","R3","R4","R5","R6"]. Need maybe include R1? Yes. The answer fields exactly: decision, currency, gross_pay, employee_contribution, allowed_deduction, taxable_pay, income_tax, net_pay, clauses. Optional explanation permitted but not needed. Ensure money strings two decimals. decision "calculate". currency "LCR".

Need consider authoritative schedule: "When supplied, its numeric values replace defaults above for that case only." We used. Need cite R1? The schedule is in R1. Good.

Let's double-check arithmetic with decimal. Employee contribution: rate 0.08, cap 4500.00, gross 4481.05. 4481.05 * 0.08 = 358.484. Round half-up: 358.48. Wait round-half-up with 358.484: to two decimals, third decimal is 4, so 358.48. Correct.

Taxable: 4481.05 - 358.48 = 4122.57. Allowed deduction 0.00. Tax:
Middle: upper 3000 - free 1200 = 1800. 1800*0.08 = 144.00.
Upper: 4122.57 - 3000 = 1122.57. *0.18 = 202.0626.
Sum = 346.0626. Round to two decimals: 346.06. Wait round-half-up: 346.0626, hundredths digit 6, thousandths 2. Yes 346.06. If sum were 346.065 would round to 346.07. Not here.

Net: 4481.05 - 358.48 = 4122.57; -0 = 4122.57; -346.06 = 3776.51. Good.

Need output JSON no markdown. Ensure only required fields. Use double quotes. clauses array.

Let's final.

We need answer JSON only. Need process payroll. Need use authoritative case reference schedule replacing defaults. Payroll month 2026-05 -> first-half. Schedule first-half: rate 0.08, cap 4500.00, deduction cap 400.00, free 1200.00, upper 3000.00, middle_rate 0.08, upper_rate 0.18.

Record gross_pay 4481.05, allowed_deduction 0.00.

Need calculate employee contribution: rate * min(gross, wage cap). Gross 4481.05 < cap 4500.00. Contribution = 4481.05 * 0.08 = 358.484 -> round half-up two decimals = 358.48? Let's compute: 4481.05 * 8% = 358.484. Round to 2 decimals: third decimal 4, so 358.48. Yes.

Allowed deduction 0.00. Check not exceed deduction cap 400 or gross - contribution = 4481.05 - 358.48 = 4122.57, so 0 ok.

Taxable pay = gross - employee_contribution - allowed_deduction = 4481.05 - 358.48 = 4122.57.

Income tax progressive:
Tax-free amount = 1200.00 untaxed.
Upper bracket begins = 3000.00. Middle rate 0.08 on portion above free up to upper: 3000 - 1200 = 1800.00 * 0.08 = 144.00.
Upper portion above 3000: taxable pay 4122.57 - 3000 = 1122.57 * 0.18 = 202.0626. Round? R2 says do not round intermediate bracket products separately before summing income tax. Sum = 144 + 202.0626 = 346.0626. Round total under R2 = 346.06 (third decimal 2? 346.0626 -> 2 decimals: 346.06 because hundredths = 6? Let's see 346.0626: digits 346 . 0 6 2 6. To two decimals, third decimal is 2, so 346.06). Yes.

Net pay = gross - employee contribution - allowed deduction - income tax = 4481.05 - 358.48 - 0 - 346.06 = 3776.51? Compute: 4481.05 - 358.48 = 4122.57. minus 346.06 = 3776.51. Yes.

Need answer fields: decision, currency, gross_pay, employee_contribution, allowed_deduction, taxable_pay, income_tax, net_pay, clauses. Optional explanation permitted but likely not needed. Clauses support calculation: cite R1 through R6. No R9. Need include R1? Calculated answers cite R1 through R6. So clauses ["R1","R2","R3","R4","R5","R6"]. Money strings two decimals.

Need ensure no Markdown fences. Return exactly JSON object. Could include explanation? Not necessary. Need only required answer fields and clauses. Allowed answer fields: calculate uses decision, currency, gross_pay, employee_contribution, allowed_deduction, taxable_pay, income_tax, net_pay, clauses. So output these.

Let's double-check if schedule values replace defaults for that case only. Yes.

Potential issue: R1 says reference schedule must include rate, cap, deduction, free, upper, middle_rate, upper_rate. It does. Good.

Potential issue: R2 input money non-negative decimal at most two fractional digits. gross_pay "4481.05" ok. allowed_deduction "0.00" ok.

Potential issue: R4 allowed_deduction defaults to 0.00 when omitted. Here present 0.00.

Potential issue: R7 conflict? No contract_gross_pay. No amendment. Good.

Need maybe cite R1-R6. Good.

Let's produce JSON.