> For the complete documentation index, see [llms.txt](https://developer.barchart.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.barchart.com/getting-started/subscription-types/cumulative-volume-volume-by-price.md).

# Cumulative Volume (Volume by Price)

Subscribe to `CUMULATIVE_VOLUME` to receive volume-by-price updates. Each `VolumeAtPrice` message aggregates the day's trades into a table of traded volume for each price.

Use `lastPrice`, `lastQuantity`, and `lastCumulativeVolume` to identify the latest trade. Use each `priceVolumes` entry to analyze the volume traded at a price level.

### VolumeAtPrice message example

```protobuf
volumeAtPrice {
  marketId: 1596974561793814014
  symbol: "ZCZ1"
  lastPrice: 511250000000
  lastQuantity: 1
  lastCumulativeVolume: 1039
  priceVolumes { price: 508500000000 volume: 6762 }
  priceVolumes { price: 509750000000 volume: 5632 }
  priceVolumes { price: 507250000000 volume: 3137 }
  priceVolumes { price: 516000000000 volume: 1371 }
  priceVolumes { price: 525000000000 volume: 175 }
  priceVolumes { price: 514750000000 volume: 531 }
  priceVolumes { price: 513500000000 volume: 1511 }
  priceVolumes { price: 512250000000 volume: 1240 }
  priceVolumes { price: 511000000000 volume: 1973 }
  priceVolumes { price: 518750000000 volume: 611 }
  priceVolumes { price: 521250000000 volume: 1549 }
  priceVolumes { price: 520000000000 volume: 1882 }
  priceVolumes { price: 515000000000 volume: 1655 }
  priceVolumes { price: 522500000000 volume: 1098 }
  priceVolumes { price: 513750000000 volume: 1240 }
  priceVolumes { price: 512500000000 volume: 987 }
  priceVolumes { price: 523750000000 volume: 734 }
  priceVolumes { price: 516250000000 volume: 1193 }
  priceVolumes { price: 517500000000 volume: 2521 }
  priceVolumes { price: 520250000000 volume: 1044 }
  priceVolumes { price: 511250000000 volume: 1039 }
  priceVolumes { price: 510000000000 volume: 7542 }
  priceVolumes { price: 522750000000 volume: 700 }
  priceVolumes { price: 508750000000 volume: 6267 }
  priceVolumes { price: 521500000000 volume: 995 }
  priceVolumes { price: 525250000000 volume: 17 }
  priceVolumes { price: 507500000000 volume: 3088 }
  priceVolumes { price: 524000000000 volume: 934 }
  priceVolumes { price: 511500000000 volume: 1151 }
  priceVolumes { price: 510250000000 volume: 5241 }
  priceVolumes { price: 516500000000 volume: 1377 }
  priceVolumes { price: 507750000000 volume: 5420 }
  priceVolumes { price: 509000000000 volume: 5733 }
  priceVolumes { price: 517750000000 volume: 1172 }
  priceVolumes { price: 519000000000 volume: 1592 }
  priceVolumes { price: 515250000000 volume: 1760 }
  priceVolumes { price: 514000000000 volume: 1773 }
  priceVolumes { price: 512750000000 volume: 255 }
  priceVolumes { price: 521750000000 volume: 563 }
  priceVolumes { price: 523000000000 volume: 1308 }
  priceVolumes { price: 524250000000 volume: 469 }
  priceVolumes { price: 514250000000 volume: 1134 }
  priceVolumes { price: 515500000000 volume: 706 }
  priceVolumes { price: 516750000000 volume: 698 }
  priceVolumes { price: 518000000000 volume: 1828 }
  priceVolumes { price: 520500000000 volume: 1249 }
  priceVolumes { price: 519250000000 volume: 2041 }
  priceVolumes { price: 506750000000 volume: 795 }
  priceVolumes { price: 523250000000 volume: 359 }
  priceVolumes { price: 524500000000 volume: 281 }
  priceVolumes { price: 513000000000 volume: 634 }
  priceVolumes { price: 511750000000 volume: 316 }
  priceVolumes { price: 509250000000 volume: 4107 }
  priceVolumes { price: 510500000000 volume: 4286 }
  priceVolumes { price: 508000000000 volume: 6592 }
  priceVolumes { price: 515750000000 volume: 807 }
  priceVolumes { price: 517000000000 volume: 1553 }
  priceVolumes { price: 514500000000 volume: 440 }
  priceVolumes { price: 513250000000 volume: 791 }
  priceVolumes { price: 518250000000 volume: 1645 }
  priceVolumes { price: 512000000000 volume: 1400 }
  priceVolumes { price: 519500000000 volume: 1792 }
  priceVolumes { price: 510750000000 volume: 2577 }
  priceVolumes { price: 522000000000 volume: 832 }
  priceVolumes { price: 520750000000 volume: 897 }
  priceVolumes { price: 509500000000 volume: 5852 }
  priceVolumes { price: 523500000000 volume: 770 }
  priceVolumes { price: 524750000000 volume: 123 }
  priceVolumes { price: 517250000000 volume: 1410 }
  priceVolumes { price: 507000000000 volume: 1710 }
  priceVolumes { price: 508250000000 volume: 6273 }
  priceVolumes { price: 519750000000 volume: 1759 }
  priceVolumes { price: 518500000000 volume: 839 }
  priceVolumes { price: 521000000000 volume: 912 }
  priceVolumes { price: 522250000000 volume: 972 }
}
```


---

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```
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