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Formosa Optical Technology CoROCO:5312 -1.33%83 Days Inventory is 188.26 as of Dec. 2025, which is 12% above its 10-year median of 167.43. GuruFocus rates ROCO:5312 with a GF Score™ of 83/100 and a GF Value™ of NT$108.98 (Modestly Undervalued). The stock has 4 warning signs investors should review. Among 786 Medical Devices & Instruments companies, Formosa Optical Technology Co ranks worse than 56.87% on this metric.
The historical rank and industry rank for Formosa Optical Technology Co's Days Inventory or its related term are showing as below:
ROCO:5312'
s Days Inventory Range Over the Past 10 Years
Min: 148.81 Med: 167.43 Max: 196.79
Current: 196.79
During the past 13 years, Formosa Optical Technology Co's highest Days Inventory was 196.79. The lowest was 148.81. And the median was 167.43.
ROCO:5312's Days Inventory is ranked worse than 56.87% of 786
companies
in the Medical Devices & Instruments industry
Industry Median: 179.6
vs ROCO:5312: 196.79
Inventory Turnover measures how fast the company turns over its inventory within a year.
Formosa Optical Technology Co's Inventory Turnover for the
three
months ended in Dec. 2025 was 0.48.
Inventory-to-Revenue determines the ability of a company to manage their inventory levels. It measures the percentage of Inventories the company currently has on hand to support the current amount of Revenue.
Formosa Optical Technology Co's Inventory-to-Revenue for the
three
months ended in Dec. 2025 was 0.77.
Formosa Optical Technology Co (ROCO:5312) Days Inventory Explanation
Days Inventory indicates the liquidity of the inventory. Generally, a lower Days Inventory is preferred as it indicates a shorter duration to clear off the inventory. An increase of the ratio may indicate the company's sales slowed. Similar ratios related to Days Inventory are:
1. Inventory Turnover measures how fast the company turns over its inventory within a year.
Formosa Optical Technology Co's Inventory Turnover for the
three
months ended in Dec. 2025 is calculated as
2. Inventory-to-Revenue determines the ability of a company to manage their inventory levels. It measures the percentage of Inventories the company currently has on hand to support the current amount of Revenue.
Formosa Optical Technology Co's Inventory to Revenue for the
three
months ended in Dec. 2025 is calculated as
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
Be Aware
A lot of business are seasonable. It makes more sense to compare Days Inventory from the same period in the previous year instead of from the previous quarter.
Formosa Optical Technology Co Days Inventory Related Terms
Formosa Optical Technology Co Days Inventory Historical Data
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
Formosa Optical Technology Co Days Inventory Chart
ROCO:5312 vs ISRG, BDX, MDLN: Days Inventory Comparison
For the Medical Instruments & Supplies subindustry, Formosa Optical Technology Co's Days Inventory, along with its competitors' market caps and Days Inventory data, can be viewed below:
* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.
Formosa Optical Technology Co Days Inventory vs Medical Devices & Instruments Industry
For the Medical Devices & Instruments industry and Healthcare sector, Formosa Optical Technology Co's Days Inventory distribution charts can be found below:
* The bar in red indicates where Formosa Optical Technology Co's Days Inventory falls into.
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
Formosa Optical Technology Co (ROCO:5312) has a Days Inventory of 188.26 as of Dec. 2025. Days inventory represents the average amount of days a company holds inventory before selling it. View historical data on Formosa Optical Technology Co and its competitors. This is 12% above median its historical median of 167.43. Over the past decade, Formosa Optical Technology Co's Days Inventory has ranged from 148.81 to 196.79. According to the industry distribution chart, Formosa Optical Technology Co ranks #447 out of 786 companies in the Medical Devices & Instruments industry, placing it in the top 56.9%.
Is Formosa Optical Technology Co's Days Inventory too high?
Formosa Optical Technology Co's current Days Inventory of 188.26 is 12% above median its 10-year median of 167.43. Over the past 10 years, this metric has ranged from a low of 148.81 to a high of 196.79. The Medical Devices & Instruments industry median Days Inventory is 179.60. Formosa Optical Technology Co's value of 188.26 is 4.8% above this industry median. Based on the distribution chart, Formosa Optical Technology Co ranks #447 out of 786 companies in the Medical Devices & Instruments industry, which is below the industry midpoint. Overall, Formosa Optical Technology Co has a GF Score™ of 83/100 and is considered Modestly Undervalued, reflecting its overall financial health beyond just this single metric.
How does Formosa Optical Technology Co's Days Inventory compare to ISRG and BDX?
According to the Medical Devices & Instruments industry distribution chart, Formosa Optical Technology Co ranks #447 out of 786 companies for Days Inventory. This places Formosa Optical Technology Co in the lower half of its industry. The industry median Days Inventory is 179.60. Formosa Optical Technology Co's value of 188.26 is 4.8% above this benchmark. Historically, Formosa Optical Technology Co's own Days Inventory has ranged from 148.81 to 196.79 over the past decade. While the company's 10-year median is 167.43 vs. the industry median of 179.60, Formosa Optical Technology Co has consistently been above the industry average. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Days Inventory for a Medical Devices & Instruments company?
The median Days Inventory among Medical Devices & Instruments companies is 179.60, based on 786 companies in the industry. Companies in the top quartile (top 25%) have a Days Inventory significantly above this median, while those in the bottom quartile fall well below. However, Days Inventory should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Formosa Optical Technology Co's current Days Inventory of 188.26 is 4.8% above the industry median. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Days Inventory mean?
A high Days Inventory can signal that a stock is expensive relative to its fundamentals. Days inventory represents the average amount of days a company holds inventory before selling it. View historical data on Formosa Optical Technology Co and its competitors. For the Medical Devices & Instruments industry, the median Days Inventory is 179.60 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Formosa Optical Technology Co's current Days Inventory is 188.26, which is 12% above median its own 10-year median of 167.43. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Formosa Optical Technology Co stock overvalued right now?
Based on GuruFocus' analysis, Formosa Optical Technology Co (ROCO:5312) is currently considered Modestly Undervalued. The stock's GF Value™ is NT$108.98, compared to a current price of NT$88.80 — trading 18.5% below its estimated fair value. The current Days Inventory is 188.26, which is 12% above median its 10-year median of 167.43 and 4.8% above the Medical Devices & Instruments industry median of 179.60. Formosa Optical Technology Co's overall GF Score™ is 83/100 with 4 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Days Inventory calculated?
Days Inventory is calculated from a company's financial statements. For Formosa Optical Technology Co (ROCO:5312), the current Days Inventory is 188.26 as of Dec. 2025. GuruFocus calculates this using data sourced from SEC filings and annual reports. See the calculation section and 30-year financial data on this page for the full breakdown.
Is Formosa Optical Technology Co (ROCO:5312) Overvalued in 2026?
Based on GuruFocus' analysis, Formosa Optical Technology Co stock appears to be undervalued.
The current stock price of NT$88.80 is trading 18.5% below its estimated GF Value™ of NT$108.98.
GuruFocus considers Formosa Optical Technology Co to be Modestly Undervalued.
Key valuation signals for ROCO:5312:
Days Inventory: 188.26 (12% above median its 10-year median of 167.43)
GF Value™: NT$108.98 vs. price of NT$88.80 (18.5% below fair value)
Industry Position: 4.8% above the Medical Devices & Instruments median (#447 of 786)
No single metric tells the full story. See the ROCO:5312 stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Formosa Optical Technology Co Business Description
Formosa Optical Technology Co Ltd is mainly engaged in the eyewear business, including optometry services and the retail business selling contact lenses and eye drops. The Group mainly derives revenue from the business divisions of Formosa Optical Technology and Bo Wei Optical, with Formosa Optical Technology generating maximum revenue. The majority of revenue is derived from the sale of glasses. The Group generates the majority of its revenue from Taiwan.
83GF Score
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