SKHY Premium Calculator / Methodology

SKHY Premium Data Methodology: Sources, Refresh Timing and Data Rules

This page explains where the SKHY Premium calculator gets its data, when it refreshes, and how precision and missing data are handled. For the calculation formulas and a step-by-step tutorial, read How to Calculate ADR Premium: Step-by-Step Guide.

Data sources

Data pointSourceRefreshed
SKHY ADR priceNasdaqUS trading hours
000660 share priceKorea Exchange (KRX)Korean trading hours
USD/KRW exchange rateFX data feedWhile a market is open
10 ADS = 1 share ratioSEC prospectusStatic

Refresh timing and missing data

The configured external scheduler (cron) calls the quote refresh endpoint once per minute while markets are active, and each successful refresh stores a new snapshot. Concretely, SKHY updates during Nasdaq's regular session (9:30–16:00 US Eastern), 000660 during KRX trading hours (09:00–15:30 Korea time), and the exchange rate whenever at least one market is open.

Nasdaq and KRX generally do not overlap, and each data source only updates during its own market window, so a closed-market value is retained with its original quote time rather than refreshed as a new observation. Each displayed result therefore compares the shown observations, which may have different timestamps. If SKHY, 000660, or USD/KRW is missing or invalid, the result is shown as unavailable rather than estimated.

Precision and freshness

Calculations use unrounded positive numeric inputs; rounding is for display. Source availability and delay can change, so the site uses “Latest” unless the displayed source and session support a stronger label.

Official ratio source

The final SEC prospectus confirms SKHY, 000660, and the ADS ratio. Review the SK Hynix ADR guide, US access guide, or return to the SKHY premium calculator.