Bollinger Bands on PSX charts, with MEBL

Bollinger Bands (bollinger bands PSX; bollinger bands kya hain) draw three lines on a price chart: a 20-day simple moving average of the close, and two lines 2 standard deviations above and below it. The standard deviation measures how widely the last 20 closes were spread. On 16 October 2026, MEBL closed at Rs 545.82. Its 20-day average was Rs 549.22, its upper band Rs 556.25 and its lower band Rs 542.19. The bands were 2.56% of the average apart, the second-narrowest reading of the past 230 sessions. That is a measurement of past volatility, not a forecast. You can add the bands free in SuperX Charts, with no account.

What are Bollinger Bands made of?

John Bollinger developed them, and StockCharts’ reference gives the default settings: a 20-day simple moving average as the middle band, and an upper and a lower band at 20-day SMA plus and minus 2 times the 20-day standard deviation of price. It calls them “volatility bands placed above and below a moving average”.

Line	Formula	What it measures
Middle band	Average of the last 20 closes	The recent level of the price
Upper band	Middle band + 2 × standard deviation of the last 20 closes	The level 2 spreads above the average
Lower band	Middle band − 2 × standard deviation of the last 20 closes	The level 2 spreads below the average
Band width	(upper − lower) ÷ middle × 100	The spread of the closes as a percent of their average

The standard deviation has one choice in it. The “population” form divides the squared gaps by 20, and the “sample” form divides by 19. SuperX Charts’ code uses the population form. StockCharts’ page does not say which it uses, and other vendors were not checked, so a figure on another site can differ in the second decimal. For MEBL on 16 October 2026, the sample form would give bands of 556.43 and 542.01 instead of 556.25 and 542.19.

How are the bands calculated for MEBL?

The data is the one-year daily series of MEBL (Meezan Bank) from SuperX’s public API: 249 bars from 17 October 2025 to 16 October 2026. The 20 closes ending on 16 October 2026 are:

Date	Close	Date	Close
21 Sep	550.98	5 Oct	548.11
22 Sep	550.42	6 Oct	552.30
23 Sep	555.51	7 Oct	550.10
24 Sep	551.66	8 Oct	548.53
25 Sep	548.12	9 Oct	548.45
28 Sep	549.23	12 Oct	541.32
29 Sep	549.93	13 Oct	542.81
30 Sep	554.91	14 Oct	545.37
1 Oct	553.65	15 Oct	548.45
2 Oct	548.79	16 Oct	545.82

Take it in steps.

1. The 20 closes add up to Rs 10,984.46. Divided by 20, the average is 549.22.
2. Each close minus 549.22, squared and added, gives 246.99. Divided by 20, that is 12.35.
3. The square root of 12.35 is the standard deviation: 3.51.
4. Two standard deviations are 7.03. The upper band is 549.22 + 7.03 = 556.25. The lower band is 549.22 − 7.03 = 542.19.
5. The width is 556.25 − 542.19 = 14.06, which is 14.06 ÷ 549.22 × 100 = 2.56% of the middle band.

The close of Rs 545.82 sat 3.63 above the lower band, which is 0.26 of the way from the lower band to the upper band. SuperX Charts has an indicator for that ratio, called Bollinger %B. Over MEBL’s 230 daily readings from 13 November 2025 to 16 October 2026, the close was inside the bands on 204 sessions (88.7%), above the upper band on 20 and below the lower band on 6. StockCharts says the bands “should contain 88-89% of price action”. They did here, which is a description of this share’s closes and not a rule for the next one.

The MEBL share page shows the same close, Rs 545.82 on 16 October 2026, down 0.48% on the day and up 20.2% over one year.

What does band width measure?

Band width is the spread of recent closes, written as a percent of their average. A narrow band means the last 20 closes sat close together. A wide band means they did not. It is a statement about size, not direction: a share that rose steadily for 20 sessions can have a wide band, and one that moved sideways can have a narrow one.

MEBL’s own year shows the range. Its band width was 22.84% on 10 April 2026, the widest of the 230 readings, and the median reading was 9.12%. It was 12.40% on 22 July 2026, 11.98% on 20 August, 8.30% on 18 September and 4.57% on 2 October. It fell to 2.61% on 9 October and to 2.55% on 15 October 2026, the lowest of the 230. The five lowest readings were all between 8 and 16 October 2026. In the last 20 sessions, closes ranged from Rs 541.32 to Rs 555.51, which is Rs 14.19 or 2.6% of the average.

What is a Bollinger squeeze?

A squeeze is a period when the bands are unusually narrow. StockCharts describes it as occurring when volatility falls to a low level, as shown by narrowing bands, and measures it with the related Bollinger BandWidth indicator, (upper band − lower band) ÷ middle band × 100. That is the formula used above.

On 16 October 2026, MEBL’s reading of 2.56% was the second-lowest of its past year. That is all the squeeze says: the last 20 closes were tightly grouped compared with the previous 229 readings. It says nothing about the next 20 sessions. A tight group of closes can be followed by a larger move up, a larger move down, or more of the same, and the band width cannot tell you which. StockCharts itself states that the direction depends on the subsequent band break. This post treats the squeeze as a measurement of low volatility only.

Two PSX details can distort the reading. The first is the exchange’s daily price limit: a share that hits its limit for several days can show a spread that comes from the rule and not from the market. Circuit breakers and upper and lower locks explains it. The second is the cash dividend. SuperX Charts adjusts daily prices for bonus shares, rights and splits, and not for cash dividends, so an ex-dividend drop inside the 20-day window widens the bands. MEBL’s last ex-dividend date in the snapshot of 9 October 2026 was 18 August 2026 (Rs 8), outside this window. Check the ex-dates on the MEBL dividend page.

How do I add Bollinger Bands in SuperX Charts?

In Simple, open the indicators menu in the top bar and choose Bollinger Bands. It is one of four presets, and volume is shown with it. In Pro, which is on for everyone and needs no account, you can set the two inputs and add band width. The indicators guide shows each step.

1. Open MEBL with Bollinger Bands in Simple, or in Pro with band width in its own pane.
2. In Pro you can also click Indicators in the top bar, or press I, and type “bollinger” in the search.
3. Click Bollinger Bands for the three lines on the price, with the outer lines dashed. Click Bollinger bandwidth for the width in a pane under the chart, and Bollinger %B for the position of the close between the bands.
4. To change the length or the multiplier, find the indicator’s row in the legend, open its settings and use the Inputs tab. The defaults are a length of 20 and a multiplier of 2. Reset goes back to them.
5. Right-click the legend row and choose Explain this indicator for a short card in words.

A link writes the indicator as its id and its two inputs, so bb:20:2 is Bollinger Bands with a length of 20 and a multiplier of 2. The figures here are recomputed from the daily bars with the terminal’s own definitions, not read off the pane.

To repeat the calculation yourself, use Download CSV in the ⋯ menu, as the PSX historical data post describes. The same reading is useful beside a moving average, and the MACD post shows the one built from two of them. For levels read from the price alone, see support and resistance on a PSX chart.

Where to go next

The MEBL chart page on this site plots its daily closes, and the MEBL stock page shows its fundamentals. Open a second bank in SuperX Charts to compare its band width: HBL closed at Rs 290.42 on 16 October 2026 and UBL at Rs 412.53.

Frequently asked questions

What are Bollinger Bands?

They are a 20-day simple moving average of the close with two lines at 2 standard deviations above and below it. The distance between the outer lines shows how widely the last 20 closes were spread.

How are Bollinger Bands calculated?

Middle band = average of the last 20 closes. Upper and lower bands = the middle band plus and minus 2 standard deviations. For MEBL on 16 October 2026, that gave 549.22, 556.25 and 542.19.

What is a Bollinger squeeze?

It is a period when the bands are unusually narrow, which means volatility has been low. It shows the size of recent moves, not their direction.

What is a normal Bollinger band width?

It depends on the share and the period. MEBL’s band width ranged from 2.55% to 22.84% over 230 sessions, with a median of 9.12% (to 16 October 2026).

How do I add Bollinger Bands in SuperX Charts?

In Simple, choose Bollinger Bands from the indicators menu. In Pro, press I, type “bollinger” and click the row, then set the length and multiplier under Inputs.

Education, not investment advice.