XBI · WMTMT

Aug 21, 2024Feb 24, 2025Aug 26, 2025Feb 25, 2026Aug 26, 2026

Breadth

101 / 147

stocks rose with the index

Concentration

13%

of the gain from MRNA, TWST, SRRK

Biggest driver

MRNA +4.33

MODERNA INC, +72.72%

Biggest drag

SRPT −5.90

SAREPTA THERAPEUTICS INC, −86.43%

What drove it

147 members · drivers first · 2Y · residual 2072.0bp exceeds 60bp gate

The XBI rose 65.38% (+66.57 pts) over two years on a mixed tape; MRNA, TWST, SRRK did most of the lifting, with 13% of the gain between them.

Read the latest market-close note: A Flat Headline on the S&P 500 Masks a Split Between Goldman Sachs and Apple

+81.5 pts from 111 gainers−21.6 pts from 36 losers

net +66.6 pts · gainers outweigh losers 3.8 to 1

Stock

Points

Return

XBIsum of all 147 stocks

+66.6

+65.38%

MRNAMODERNA INC

+4.3

+72.72%

TWSTTWIST BIOSCIENCE CORP

+2.2

+243.12%

SRRKSCHOLAR ROCK HOLDING CORP

+1.9

+548.38%

RYTMRHYTHM PHARMACEUTICALS INC

+1.9

+146.52%

ERASERASCA INC

+1.9

+574.30%

CGONCG ONCOLOGY INC

+1.8

+114.50%

APGEAPOGEE THERAPEUTICS INC

+1.8

+179.11%

ORKAORUKA THERAPEUTICS INC

+1.7

+252.28%

TVTXTRAVERE THERAPEUTICS INC

+1.6

+672.38%

SYRESPYRE THERAPEUTICS INC

+1.6

+252.30%

DNTHDIANTHUS THERAPEUTICS INC

+1.6

+288.22%

MDGLMADRIGAL PHARMACEUTICALS INC

+1.5

+110.36%

RVMDREVOLUTION MEDICINES INC

+1.5

+375.80%

NTRANATERA INC

+1.4

+176.20%

TGTXTG THERAPEUTICS INC

+1.4

+119.51%

117 othersclick to expand the full index

+49.8

SPRYARS PHARMACEUTICALS INC

−0.4

−55.00%

RXRXRECURSION PHARMACEUTICALS A

−0.4

−54.20%

BHVNBIOHAVEN LTD

−0.5

−58.90%

NTLAINTELLIA THERAPEUTICS INC

−0.6

−44.13%

CATXPERSPECTIVE THERAPEUTICS INC

−0.6

−79.44%

MPLTMAPLIGHT THERAPEUTICS INC

−0.7

−29.88%

DYNDYNE THERAPEUTICS INC

−0.8

−43.96%

MYGNMYRIAD GENETICS INC

−0.8

−88.83%

JBIOJADE BIOSCIENCES INC

−0.8

−59.91%

ALTALTIMMUNE INC

−1.0

−54.15%

GERNGERON CORP

−1.0

−66.30%

SMMTSUMMIT THERAPEUTICS INC

−1.1

+6.67%

CAPRCAPRICOR THERAPEUTICS INC

−1.4

+104.37%

RAREULTRAGENYX PHARMACEUTICAL IN

−2.1

−53.65%

SRPTSAREPTA THERAPEUTICS INC

−5.9

−86.43%

Cap weighting, illustrated

ULTRAGENYX PHARMACEUTICAL IN and ADMA BIOLOGICS INC moved almost identically (−53.65% vs −46.02%), yet RARE moved the XBI 105.3× as much. In a cap-weighted index, the bigger company's weight turns the same percentage move into far more points.

Attribution map

slicing the +66.57 pt move · cell size = points contributed · color = direction, intensity = return

SRPT−5.9 pts(−86.4%)

MRNA+4.3 pts(+72.7%)

TWST+2.2 pts(+243.1%)

RARE−2.1 pts(−53.7%)

SRRK+1.9 pts(+548.4%)

RYTM+1.9 pts

ERAS+1.9 pts

CGON+1.8 pts

APGE

ORKA+1.7 pts(+252.3%)

TVTX+1.6 pts

SYRE+1.6 pts

DNTH+1.6 pts

MDGL+1.5 pts

RVMD

CAPR−1.4 pts

NTRA+1.4 pts

TGTX

SLS

KRYS

PRAX

ROIV

PTGX+1.3 pts

GRAL+1.3 pts

KYMR

HALO

VRDN+1.2 pts

CELC+1.2 pts

COGT

BEAM

SMMT−1.1 pts

NVAX+1.1 pts

RLAY

GERN

INCY

ACAD

ARQT

GILD

EXEL

IMVT

AMGN+0.9 pts

PURR+0.9 pts

JBIO−0.8 pts

MIRM+0.8 pts

ZBIO

IBRX

DNLI

QURE

MPLT

TRAX

MLYS

CATX

IDYA

IMNM

IONS

BHVN

CDNA

AVTX

RIGL

RXRX

XNCR

IMMX

ABSI

Concentration curve

cumulative share of the +66.57 pt move · sorted by contribution

When they drove it

cumulative points through the period

Breadth

member returns, this period

−100%+100%+300%+500%+700%+900%+1,100%+1,300%

From −88.83% (MYGN) to +1,309.68% (KOD). Equal-weight, the XBI would be +168.68% vs the actual +65.38%; the gap is what cap weighting did.

By sector

point contribution · sums to +66.57 pts

-147

+59.9

The year, session by session

every trading day of 2026 · hover for the move

JANFEBMARAPRMAYJUNJULAUG

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SPDR S&P Biotech ETF

What drove it

Attribution map

Concentration curve

When they drove it

Breadth

By sector

The year, session by session

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