fifo-calculator

FIFO Calculation for Cost of Goods Sold

How To Use

This library exports a single function that expects an ordered series of quantity and costPerItem and returns the quantity on hand and value on hand after each of the movements. If a movement decreases stock, it adds a breakdown of costs related to that decrease based the costs associated with increasing that stock following the FIFO strategy.

Expected Input

[
  {
    "quantity": 1.0,
    "costPerItem": 10.0,
  },
  {
    "quantity": -1.0,
    "costPerItem": 0.0,
  },
  {
    "quantity": 10.0,
    "costPerItem": 5.0,
  },
  {
    "quantity": 10.0,
    "costPerItem": 6.0,
  },
  {
    "quantity": 5.0,
    "costPerItem": 7.0,
  },
  {
    "quantity": -23.0,
    "costPerItem": 0.0,
  },
  {
    "quantity": 100.0,
    "costPerItem": 8.0,
  },
  {
    "quantity": -10.0,
    "costPerItem": 0.0,
  },
  {
    "quantity": -20.0,
    "costPerItem": 0.0,
  },
  {
    "quantity": -10.0,
    "costPerItem": 0.0,
  },
]

Output

[
    {
      "quantity": 1.0,
      "costPerItem": 10.0,
      "quantityOnHand": 1.0,
      "valueOnHand": 10.0,
    },
    {
      "quantity": -1.0,
      "quantityOnHand": 0.0,
      "valueOnHand": 0.0,
      "costs": [
        {
          "cost": 10.0,
          "quantity": 1.0
        },
      ],
    },
    {
      "quantity": 10.0,
      "costPerItem": 5.0,
      "quantityOnHand": 10.0,
      "valueOnHand": 50.0,
    },
    {
      "quantity": 10.0,
      "costPerItem": 6.0,
      "quantityOnHand": 20.0,
      "valueOnHand": 110.0,
    },
    {
      "quantity": 5.0,
      "costPerItem": 7.0,
      "quantityOnHand": 25.0,
      "valueOnHand": 145.0,
    },
    {
      "quantity": -23.0,
      "quantityOnHand": 2.0,
      "valueOnHand": 14.0,
      "costs": [
        {
          "cost": 5.0,
          "quantity": 10.0
        },
        {
          "cost": 6.0,
          "quantity": 10.0
        },
        {
          "cost": 7.0,
          "quantity": 3.0
        }
      ]
    },
    {
      "quantity": 100.0,
      "costPerItem": 8.0,
      "quantityOnHand": 102.0,
      "valueOnHand": 814.0,
    },
    {
      "quantity": -10.0,
      "quantityOnHand": 92.0,
      "valueOnHand": 736.0,
      "costs": [
        {
          "cost": 7.0,
          "quantity": 2.0
        },
        {
          "cost": 8.0,
          "quantity": 8.0
        },
      ],
    },
    {
      "quantity": -20.0,
      "quantityOnHand": 72.0,
      "valueOnHand": 576.0,
      "costs": [
        {
          "cost": 8.0,
          "quantity": 20.0
        },
      ],
    },
    {
      "quantity": -10.0,
      "quantityOnHand": 62.0,
      "valueOnHand": 496.0,
      "costs": [
        {
          "cost": 8.0,
          "quantity": 10.0
        },
      ],
    },
  ]

Test

Runs tests using Jest

yarn test