# Discounted Present Value – Local Finite-Change Elasticity Calculator

> Discounted Present Value – Local Finite-Change Elasticity Calculator is a paid API for AI agents from market.datapackvibe.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-22).

Calculates how discounted present value (PV) responds to a small percentage change in a specified input (future value, interest rate, or time horizon) using local finite-change elasticity approximation.

## Facts

- Endpoint: POST https://market.datapackvibe.com/x402/assistant-finance-present-value-elasticity?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/discounted-present-value-local-finite-change-elasticity-calculator-88a6b220
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_QaNf0Qh0KATALBpP8HKD8

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability discounted-present-value-local-finite-change-elasticity-calculator-88a6b220 -d '<json body>'
```

Example prompt: For a payment of $12,000 due in 2 years at a 5% annual effective rate, calculate how sensitive the discounted present value is to a 1% change in the future_value — give me the local finite-change elasticity with formula and limitations.

## When to prefer this

Choose this endpoint when you need a local sensitivity/elasticity measure for discounted present value around a specific baseline scenario — particularly when you want a finite-difference approximation rather than an analytical derivative, and when you need the result with explicit formula and limitation documentation. Prefer this over general financial calculators when the specific output is an elasticity coefficient for PV analysis.

## Known failure modes

- Invalid field name not in enum (future_value, annual_effective_rate_percent, years)
- annual_effective_rate_percent outside allowed range -99 to 100
- years outside allowed range 0 to 100
- future_value outside allowed range ±1,000,000,000,000
- step_percent outside allowed range 0.01 to 10
- Baseline field value is zero (elasticity undefined for zero denominator)
- Payment failure or insufficient USDC balance

## How this service works

Discounted present value - Local finite-change elasticity: Measure output response to a supplied small percentage change in one nonzero input; local approximation. Metric: Discounted present value. Supplied figures only; returns JSON with formula, units and limitations. One of 50 calculators with 20 analysis modes. No live feed, financial advice or trade execution. 0.01 USDC includes one bounded local finite-change elasticity report.

## Output

Returns a JSON object containing the computed local finite-change elasticity coefficient of discounted present value with respect to the specified input field, along with the formula used, units, and a description of limitations of the local approximation.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "field": {
   "enum": [
    "future_value",
    "annual_effective_rate_percent",
    "years"
   ],
   "type": "string",
   "default": "future_value"
  },
  "baseline": {
   "type": "object",
   "default": {
    "years": 2,
    "future_value": 12000,
    "annual_effective_rate_percent": 5
   },
   "required": [
    "future_value",
    "annual_effective_rate_percent",
    "years"
   ],
   "properties": {
    "years": {
     "type": "number",
     "default": 2,
     "maximum": 100,
     "minimum": 0,
     "description": "Amount in a consistent supplied currency and reporting period"
    },
    "future_value": {
     "type": "number",
     "default": 12000,
     "maximum": 1000000000000,
     "minimum": -1000000000000,
     "description": "Amount in a consistent supplied currency and reporting period"
    },
    "annual_effective_rate_percent": {
     "type": "number",
     "default": 5,
     "maximum": 100,
     "minimum": -99,
     "description": "Percent units: enter 5 for 5%, not 0.05"
    }
   },
   "additionalProperties": false
  },
  "step_percent": {
   "type": "number",
   "default": 1,
   "maximum": 10,
   "minimum": 0.01
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/discounted-present-value-local-finite-change-elasticity-calculator-88a6b220/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from market.datapackvibe.com](https://www.zero.xyz/host/market.datapackvibe.com/llms.txt)