Nifty 50 — if the first 30 min move exceeds 150 pts, how often does it stay beyond 150 at the close?

Data: Nifty 50 index 1-min candles (Upstox, NSE_INDEX|Nifty 50), 2022-10-10 → 2026-10-09, 987 regular sessions (excluded special/partial sessions: 2024-03-02, 2024-05-18, 2025-10-21). Built 2026-10-09 20:23 IST.

UP days (09:45 ≥ open+150)
50% held at close
8/16, 95% CI 28–72% · never retraced: 19%
DOWN days (09:45 ≤ open−150)
50% held at close
9/18, 95% CI 29–71% · never retraced: 28%
Event frequency
34 of 987 days
3.4% of sessions · close same side as open: 76%
Definitions. open = 09:15 candle open; p30 = close of the 09:44 candle (price at 09:45); move30 = p30 − open; event if |move30| > 150. close = close of 15:29 candle. Held: close − open ≥ 150 (up) / open − close ≥ 150 (down). Strict: no 1-min low (up) / high (down) from 09:45 to 15:30 came back inside 150 of the open. Same side: close > open (up) / < open (down). Extension = close − p30 in the event direction (negative = retrace). MAE = worst adverse move from p30 after 09:45 (pts). %-variant: threshold 0.65% of open (150 pts ≈ 0.68% of open on average). Gap variant: same rules with the previous session close as base. CIs: Wilson 95%. Small samples — read CIs.

Headline table

VariantDirnHeld at closeNever retraced (strict)Close same side as baseMedian ext. 09:45→close [p25,p75]Median MAE after 09:45 [p75/p90]
150 pts from 09:15 open (main)up1650% (8/16; CI 28–72%)19% (3/16; CI 7–43%)75% (12/16; CI 51–90%)-45 [-221, +56]183 [277 / 373]
150 pts from 09:15 open (main)down1850% (9/18; CI 29–71%)28% (5/18; CI 12–51%)78% (14/18; CI 55–91%)-36 [-176, +66]124 [232 / 321]
150 pts from 09:15 open (main)all3450% (17/34; CI 34–66%)24% (8/34; CI 12–40%)76% (26/34; CI 60–88%)-43 [-211, +67]132 [269 / 373]
0.65% of open from 09:15 openup1464% (9/14; CI 39–84%)21% (3/14; CI 8–48%)79% (11/14; CI 52–92%)-21 [-200, +91]171 [269 / 340]
0.65% of open from 09:15 opendown1942% (8/19; CI 23–64%)32% (6/19; CI 15–54%)74% (14/19; CI 51–88%)-51 [-173, +55]128 [222 / 313]
0.65% of open from 09:15 openall3352% (17/33; CI 35–67%)27% (9/33; CI 15–44%)76% (25/33; CI 59–87%)-47 [-200, +77]128 [262 / 347]
150 pts from previous close (gap incl.)up7276% (55/72; CI 65–85%)42% (30/72; CI 31–53%)99% (71/72; CI 93–100%)+18 [-65, +92]74 [146 / 212]
150 pts from previous close (gap incl.)down7659% (45/76; CI 48–70%)34% (26/76; CI 25–45%)95% (72/76; CI 87–98%)-11 [-107, +86]91 [184 / 274]
150 pts from previous close (gap incl.)all14868% (100/148; CI 60–75%)38% (56/148; CI 30–46%)97% (143/148; CI 92–99%)+5 [-90, +92]81 [155 / 234]

Intraday paths of event days

By year (150-pt, from open)

YearDirnHeldStrictSame sideMedian extMedian MAE
2023down21 (50%; CI 9–91)0 (0%)2 (100%)-86100
2024down94 (44%; CI 19–73)3 (33%)7 (78%)-25197
2024up30 (0%; CI 0–56)0 (0%)0 (0%)-235262
2025down21 (50%; CI 9–91)0 (0%)1 (50%)-40140
2025up106 (60%; CI 31–83)2 (20%)9 (90%)+1115
2026down53 (60%; CI 23–88)2 (40%)4 (80%)+12128
2026up32 (67%; CI 21–94)1 (33%)3 (100%)-114272

2022 (10 Oct–30 Dec, 57 sessions): no events. 2023 had no up events.

move30 vs close − open

Event days (150 pts from open)

DateDirOpen 09:15p30 09:45move30CloseClose−openHeld?Strict?ExtMAE
2023-01-31down17731.4517578.25-153.217682.55-48.9nono-104120
2023-04-17down17863.0017636.60-226.417704.10-158.9YESno-6880
2024-01-17up21647.2521812.45+165.221577.25-70.0nono-235262
2024-05-13down22027.9521857.40-170.622119.40+91.5nono-262274
2024-06-03down23337.9023105.70-232.223305.95-31.9nono-200203
2024-06-04down23179.5022584.15-595.421996.45-1183.0YESYES+588297
2024-06-05down22128.3521932.45-195.922573.00+444.6nono-641738
2024-10-03up25452.8525616.75+163.925266.00-186.8nono-351386
2024-10-17down25027.4024850.20-177.224750.20-277.2YESYES+10010
2024-10-21down24956.1524772.25-183.924739.45-216.7YESno+33107
2024-11-04down24315.7524069.75-246.023990.95-324.8YESYES+794
2024-11-18down23605.3023368.35-236.923465.30-140.0nono-97197
2024-11-19up23529.5523702.60+173.123468.70-60.9nono-234238
2024-11-21down23488.4523321.60-166.823346.75-141.7nono-2555
2025-02-28down22433.4022261.70-171.722127.40-306.0YESno+13439
2025-03-05up22073.0522237.60+164.622346.65+273.6YESno+10926
2025-03-06down22476.3522315.15-161.222529.20+52.9nono-214241
2025-03-17up22353.1522553.20+200.122515.25+162.1YESno-38111
2025-04-01up23341.1023545.10+204.023179.70-161.4nono-365409
2025-04-07up21758.4022021.70+263.322238.00+479.6YESno+216225
2025-04-11up22695.4022849.00+153.622844.50+149.1nono-4113
2025-05-02up24311.9024529.85+217.924313.65+1.8nono-216291
2025-05-07up24233.3024402.85+169.624409.30+176.0YESno+6118
2025-05-09up23935.7524090.50+154.824038.65+102.9nono-52141
2025-05-12up24420.1024591.70+171.624920.25+500.1YESYES+329-1
2025-11-26up25842.9526024.10+181.226203.50+360.6YESYES+1790
2026-01-13down25897.3525730.20-167.225714.20-183.2YESno+1697
2026-02-03down26308.0525727.30-580.825714.80-593.2YESYES+12136
2026-03-02up24659.2524963.65+304.424849.75+190.5YESno-114360
2026-03-25up23064.4023270.90+206.523309.00+244.6YESYES+3824
2026-04-06down22780.3022620.20-160.122959.45+179.2nono-339378
2026-05-04up24063.5524276.65+213.124123.80+60.2nono-153272
2026-06-30down24032.0523870.35-161.723917.75-114.3nono-47128
2026-09-28down23064.9022857.40-207.522780.25-284.6YESYES+7729

Files: event_days_150pts.csv, event_days_pct065.csv, event_days_gap_prevclose.csv, per_year_150pts.csv, per_year_pct065.csv, all_days_summary.csv, summary.json. Research only; not a trading recommendation.