Haircut, Corridor and Settlement

PXS promises no price. What the protocol has instead is a procedure: how a PXS converts into PIXA, and how much less it delivers when the PXS outside the treasury grows large against all PIXA. That reduction is the haircut. This page sets out the procedure in both directions, derives the haircut from the code, compares the design's corridor with the chain's thresholds, and shows how far the network stands from each.

Three numbers decide everything

P is current_supply in condenser_api.get_dynamic_global_properties. S is current_pxs_supply in the same call, less the pxs_balance of pixa.omnibus from condenser_api.get_accounts. m is market_median_history in condenser_api.get_feed_history, the median before any haircut.

Two ratios follow from them:

• Collateral ratio R = P ÷ (S × m): the value of all PIXA divided by the value of the PXS outside the treasury, both at the median feed. About 804 on 2026-10-06 and 155 on 2026-11-03.
• Debt ratio d = 1 ÷ (1 + R): the PXS outside the treasury as a share of the combined value. 0.124% on 2026-10-06 and 0.641% on 2026-11-03.

The treasury's PXS counts in neither ratio. The chain leaves it out of the debt ratio (database.cpp:2918-2941) and out of the haircut (2502-2505). The thresholds themselves are on Chain Parameters.

Converting PXS into PIXA

convert takes the PXS from your balance at once. 3.5 days later, the chain burns it and pays you PIXA at the median feed in force at that moment, which already includes any haircut. There is no fee (database_conversion.cpp:49-71).

• The rate is fixed at the end, not at the start. No one knows it when the request is made. This is deliberate: a converter cannot use news that the median has not absorbed yet. Steem's 2016 whitepaper gave the same reason for its one-week delay (From SBD to PXS).
• A real conversion. On 2026-09-30 at 15:53:03 UTC (block 752,436), an account asked to convert 31.334 PXS. The request settled on 2026-10-04 at 03:53:00 UTC (block 853,232) for 1,624.135 PIXA, which is 31.334 × 51.833.

Converting PIXA into PXS

collateralized_convert works in two steps (hive_evaluator_transfer.cpp:539-586, database_conversion.cpp:76-120):

1. At once. You lock an amount of PIXA as collateral. The chain converts half of it into PXS at whichever of the last 84 hourly samples gives the fewest PXS, less a 5% fee, and pays you the PXS immediately.
2. 3.5 days later. The chain works out what your PXS cost at the market median then, plus the 5% fee. It burns that much PIXA and returns the rest of the collateral. The market median is the median without any haircut.

The chain refuses the conversion while printing is stopped, or if the new PXS would take the debt ratio past 20% (hive_evaluator_transfer.cpp:551, 579-580). If by then the market median is more than twice the sample used at the start, meaning PIXA has lost more than half its value against a Big Mac, the collateral no longer covers the cost: the chain keeps all of it and records a warning (database_conversion.cpp:95-102).

A real conversion. On 2026-09-24 at 10:10:18 UTC (block 572,803), an account locked 230,769.130 PIXA and received 2,120.079 PXS at once: half the collateral, 115,384.565 PIXA, at 51.833 × 1.05 = 54.42465 PIXA per PXS. On 2026-09-27 at 22:10:15 UTC (block 673,588) the conversion settled. The chain burned 115,384.557 PIXA and returned 115,384.573.

When printing stops

While the debt ratio is under 20%, the chain prints PXS: authors receive the PXS half of their rewards in PXS (Posting and Rewards). At 20% or above, it stops. That half is then paid in PIXA, and new PIXA → PXS conversions are refused (database.cpp:2943-2964, 965-1009).

• The switch is a step. Hive's hardfork 26 placed the start and the end of the reduction both at 20%, so the print rate is either 100% or 0.
• In collateral terms, printing stops when R falls to 4.
• The fund's share keeps arriving. Each block's share for the Decentralized Pixa Fund is converted into PXS whatever the print rate (database.cpp:1783-1787). It lands in the treasury, outside both ratios.
• The fund keeps paying. Approved proposals are paid in PXS from the treasury whatever the print rate (dhf_processor.cpp:161-212). Once paid out, that PXS counts in both ratios, so the PXS outside the treasury can keep growing while printing is stopped.

The haircut

Every hour, after taking the new median, the chain asks whether the PXS outside the treasury would be worth more than 30% of the combined value at that median. If so, it replaces the median with the price at which that PXS is worth exactly 30% (database.cpp:2480-2529):

corrected price = 70 × S  PXS  per  30 × P  PIXA

One PXS then converts into 3P ÷ 7S PIXA, which is less than m. As a share of what the feed names:

haircut factor = min( 1 , 3R ÷ 7 )

• It is 1 while R is at least 7/3, about 2.33. Below that it falls in a straight line toward zero: 0.86 at R = 2, 0.43 at R = 1.
• It applies at settlement. A convert requested before the haircut and settling while it is in force gets the corrected rate.
• It applies wherever the chain uses the median: convert, the fund's share of issuance, PIXA sent to the treasury, and the chain's own valuation of PXS. Only the second step of a PIXA → PXS conversion uses the market median without it.
• It is not permanent. The chain recomputes it every hour from the market median. When R rises above 7/3 again, the next sample removes it.

What it limits. At the corrected price, all PXS outside the treasury is worth exactly 3/7 of all PIXA, or 30% of the combined value. Conversions settling at that price can create at most 3P ÷ 7 PIXA. Each hour the chain recomputes the correction from the new P and S, and as conversions burn PXS and add PIXA it relaxes. The haircut therefore slows dilution and reduces its total, without ending it. The code states its purpose: to stop someone holding a large amount of the debt token from using "sharp decline in HIVE price" to convert into the liquid token "and take over the blockchain" (database.cpp:2482-2486).

Corridor and thresholds: design and chain

The PXS design notes describe three regimes of the collateral ratio, and a haircut that falls "linearly toward zero" below the lower edge. The chain enforces other numbers:

Four differences matter:

• The lower edge. The design's haircut starts below 3. The chain's starts below 7/3, about 2.33.
• The print stop. At 4, the chain stops paying authors in PXS and refuses new conversions into PXS, inside what the design calls the viable corridor. The design notes do not mention it.
• The upper edge. The chain has none. Every threshold is a constant compiled into hived, which changes only by a hardfork, at any ratio (Protocol Upgrades).
• Thirty per cent of what. The design says "the Supra's weight" must never exceed "~30% of the Atlas's strength", and calls this "exactly equivalent" to a ratio of 3. Thirty per cent of the Atlas is R = 3.33. The chain's 30% is a share of the combined value, R = 2.33.

The notes present the corridor as a change to Hive's machinery: "the fixed debt cap becoming a continuous haircut over a corridor". In the code, Hive's cap already is this haircut, continuous below its threshold. Pixa runs it unchanged (From SBD to PXS).

Where the network stands

On 2026-10-06, R was about 804 and the debt ratio 0.124%. On 2026-11-03, with five times as much PXS outside the treasury, R was about 155 and the debt ratio 0.641%. Both times printing was on and no haircut applied. Two facts qualify that distance.

It is measured at a placeholder. R moves in proportion to PIXA's value counted in Big Macs. On 2026-10-06 that value came from an agreed placeholder, not a market. On 2026-11-03 most witnesses read PIXA's market, but the median still rested on the placeholder that seven of them publish (Oracle and Price Feed). With the supplies of 2026-11-03, printing would stop if PIXA were worth about 39 times less, in Big Macs, than the median assumes, and the haircut would start at about 66 times less.

Most PXS sits in the treasury. pixa.omnibus held 249,266.219 PXS on 2026-10-06, 99.04% of all PXS, and 248,363.319 PXS on 2026-11-03, 95.11%. None of it counts in the ratios. PXS paid to proposals does count while its recipients hold it. If all of the treasury's PXS were outside it, R would be about 7.6 at the median of 2026-11-03: printing would stop at about 1.9 times less value in Big Macs, and the haircut would start at about 3.2 times less. The fund pays at most 1% of its balance a day, and only to proposals that stakeholders approve (Decentralized Pixa Fund).

How to tell whether the haircut applies

Shellcurl -s -X POST https://api.pixagram.com -H 'Content-Type: application/json' \
  -d '{"jsonrpc":"2.0","method":"condenser_api.get_feed_history","params":[],"id":1}'

• The two medians. The haircut is in force when current_median_history differs from market_median_history. The second is never corrected. Both were 51.833 PIXA per PXS on 2026-10-06, and both 51.000 on 2026-11-03.
• The warning. Each hour the correction applies, the chain records a system_warning virtual operation. Its text uses Hive's names: "HIVE price corrected upward due to 30% HBD cutoff rule, from … to …" (database.cpp:2517-2524).
• Printing. pxs_print_rate in condenser_api.get_dynamic_global_properties is 10000 while printing is on and 0 while it is stopped.

What the haircut does not do

• It does not set a market price. PXS has no market today: the chain's own order book for PIXA against PXS held no orders on 2026-11-03. On Steem in 2019, SBD traded below even its reduced conversion value (From SBD to PXS).
• It does not protect PXS holders. It protects PIXA holders against dilution by lowering what each PXS delivers.
• It does not act on transfers or trades. It changes what conversions at the median deliver, the fund's included, and the chain's own valuation of PXS.
• It is not a reserve. No assets are set aside, and nothing is bought or sold.

Inherited → changed

Sources

• Code, at commit 48f75a2:
  • the median and the haircut: database.cpp:2418-2533
  • the debt ratio and the print rate: database.cpp:2918-2964
  • printing in rewards: database.cpp:965-1009
  • conversions: database_conversion.cpp:34-134; hive_evaluator_transfer.cpp:523-586
  • the fee arithmetic: asset.cpp:371-417
  • the constants: config.hpp:199-202 and 365-372
• Live values, read in one batch request at block 917,250 on 2026-10-06 09:14 UTC, and in another at block 1,723,044 on 2026-11-03 08:59 UTC: condenser_api.get_dynamic_global_properties, condenser_api.get_feed_history, condenser_api.get_accounts for pixa.omnibus, database_api.list_hbd_conversion_requests, and on 2026-11-03 condenser_api.get_order_book.
• Conversions: condenser_api.get_ops_in_block for blocks 572,803, 673,588, 752,436 and 853,232.
• Hardfork dates for Steem and Hive: the hardfork_operation virtual operation in each activation block (From SBD to PXS).
• PXS design notes (Pixagram, June 2026), §4.3, §4.4 and §4.6.