SMV Improvement Percentage: Formula, Calculation, and Practical Example

 

Learn how to measure efficiency gains in garment production with a simple SMV improvement formula.

The Importance of Measuring SMV Improvement in the Garment Industry

In the garment industry, the Industrial Engineering (IE) department plays a vital role in driving factory performance through continuous improvement activities. These include increasing productivity, reducing cost per garment, optimizing work methods, and implementing effective Standard Operating Procedures (SOPs).

To measure the impact of these initiatives, the department relies on various Key Performance Indicators (KPIs). However, one important KPI that often gets overlooked is the SMV Improvement Percentage (or SMV Reduction Percentage).

What is SMV Improvement?

SMV (Standard Minute Value) represents the time required to produce one garment under standard working conditions. When the IE team reduces the SMV through method study, motion analysis, or layout optimization, it directly improves factory efficiency and lowers production cost.

Why Measure SMV Improvement?

Tracking SMV improvement helps the engineering department to:

• Quantify the results of method and layout improvements

• Highlight the effectiveness of engineering initiatives

• Support cost reduction and productivity improvement programs

• Benchmark performance between styles, lines, or factories

Formula for SMV

$$\text{SMV}=\text{(Observed Time × Rating Factor × Allowance)}$$

Or, in a more expanded and commonly used form:

$$\text{SMV} = \left( \frac{\text{Observed Time} \times \text{Performance Rating}}{100} \right) \times (1 + \text{Allowance \%})$$

Explanation of Each Term:

• Observed Time:
  The average time (in minutes or seconds) taken by an operator to perform an operation during time study.

• Performance Rating:
  A percentage factor used to adjust the observed time to a standard performance level (usually 100% means normal performance).

• Allowance (%):
  Additional time added to cover unavoidable interruptions such as fatigue, machine delays, and personal needs (commonly 10–20%).

Example:

If

• Observed Time = 0.50 minute

• Performance Rating = 110%

• Allowance = 15%

Then,

$$\text{SMV} = \left( \frac{0.50 \times 110}{100} \right) \times (1 + 0.15)$$ $$\text{SMV} = 0.55 \times 1.15 = 0.6325 \text{ minute}$$

So, the Standard Minute Value (SMV) for this operation is 0.63 minute.

Importance of Measuring SMV Improvement

While industrial engineers (IEs) primarily focus on reducing production costs, one of the most effective ways to achieve this is by reducing the Standard Minute Value (SMV) of operations. SMV reduction can be accomplished through workplace engineering, method improvement, and the use of machine attachments or guides that enhance operational efficiency.

However, achieving improvement is only half the job — measuring and recording those improvements is equally important. Here’s why:

1. Calculate the Monetary Saving:
   After introducing a new SMV, it’s essential to calculate the monetary benefit gained from the reduction. This helps quantify the impact of your engineering initiatives in financial terms.

2. Track and Validate Improvement Work:
   Every improvement project should be measured and documented. Keeping detailed records ensures your work gets recognized by management and provides data for future analysis.

3. Maintain Before-and-After Records:
   Always record the previous method, new method, and their respective SMVs—especially when the improvement results from a method change. This creates transparency and supports data-driven decision-making.

4. Support Continuous Improvement (Kaizen):
   Measuring SMV improvement aligns perfectly with the Kaizen philosophy—continuous, incremental improvement. It helps sustain a culture of ongoing efficiency enhancement.

5. Enable Easy Tracking:
   Maintaining SMV improvement data operation-wise and product-wise makes it easier to track trends, compare styles, and identify areas with the highest improvement potential.