XBI · WMTMT

Jul 27Aug 3Aug 11Aug 18Aug 25

Breadth

114 / 147

stocks rose with the index

Concentration

29%

of the gain from MRNA, TWST, IOVA

Biggest driver

MRNA +3.19

MODERNA INC, +185.51%

Biggest drag

SION −0.32

SIONNA THERAPEUTICS INC, −86.23%

What drove it

147 members · drivers first · 1M · residual 28.7bp within 60bp gate

The XBI rose 12.30% (+18.53 pts) on the month in a broad advance: 114 of 147 stocks rose, with MRNA out front at +3.19 points.

Read the latest market-close note: Nvidia and Goldman Sachs Lead a Narrow Advance as Energy and Staples Slide

+21.9 pts from 113 gainers−3.4 pts from 34 losers

net +18.5 pts · gainers outweigh losers 6.4 to 1

Stock

Points

Return

XBIsum of all 147 stocks

+18.5

+12.30%

MRNAMODERNA INC

+3.2

+185.51%

TWSTTWIST BIOSCIENCE CORP

+1.5

+74.97%

IOVAIOVANCE BIOTHERAPEUTICS INC

+0.8

+72.24%

HALOHALOZYME THERAPEUTICS INC

+0.6

+34.17%

NTRANATERA INC

+0.6

+30.49%

PURRHYPERLIQUID STRATEGIES

+0.5

+87.22%

SLSSELLAS LIFE SCIENCES GROUP I

+0.5

+30.04%

CRSPCRISPR THERAPEUTICS AG

+0.4

+30.32%

QUREUNIQURE NV

+0.4

+33.60%

REGNREGENERON PHARMACEUTICALS

+0.4

+25.08%

GRALGRAIL INC

+0.3

+23.62%

TVTXTRAVERE THERAPEUTICS INC

+0.3

+18.23%

AMGNAMGEN INC

+0.3

+18.21%

SRRKSCHOLAR ROCK HOLDING CORP

+0.3

+19.05%

BEAMBEAM THERAPEUTICS INC

+0.3

+23.77%

117 othersclick to expand the full index

+10.5

AGIOAGIOS PHARMACEUTICALS INC

−0.1

−8.30%

TNGXTANGO THERAPEUTICS INC

−0.1

−7.30%

MYGNMYRIAD GENETICS INC

−0.1

−41.47%

MDGLMADRIGAL PHARMACEUTICALS INC

−0.1

−7.09%

ALKSALKERMES PLC

−0.1

−6.68%

ARDXARDELYX INC

−0.1

−25.30%

ERASERASCA INC

−0.1

−5.88%

ARQTARCUTIS BIOTHERAPEUTICS INC

−0.2

−10.70%

ALNYALNYLAM PHARMACEUTICALS INC

−0.2

−13.76%

COGTCOGENT BIOSCIENCES INC

−0.2

−9.00%

NBIXNEUROCRINE BIOSCIENCES INC

−0.2

−13.06%

VCYTVERACYTE INC

−0.2

−20.81%

GLUEMONTE ROSA THERAPEUTICS INC

−0.3

−35.46%

MIRMMIRUM PHARMACEUTICALS INC

−0.3

−14.12%

SIONSIONNA THERAPEUTICS INC

−0.3

−86.23%

Cap weighting, illustrated

NATERA INC and MAPLIGHT THERAPEUTICS INC moved almost identically (+30.49% vs +26.60%), yet NTRA moved the XBI 28.5× 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 +18.53 pt move · cell size = points contributed · color = direction, intensity = return

MRNA+3.2 pts(+185.5%)

TWST+1.5 pts(+75.0%)

IOVA+0.8 pts(+72.2%)

HALO+0.6 pts(+34.2%)

NTRA+0.6 pts

PURR+0.5 pts

SLS+0.5 pts

CRSP

QURE+0.4 pts(+33.6%)

REGN+0.4 pts(+25.1%)

GRAL

SION

TVTX

AMGN

SRRK

BEAM+0.3 pts

IMNM+0.3 pts

ACAD

PRAX

INSM+0.3 pts

KYMR+0.3 pts

VRDN

XNCR

REPL

MIRM

CDNA

GLUE

VRTX

NTLA

ORKA

GILD

RVMD

NVAX+0.2 pts

IBRX+0.2 pts

PGEN

NBIX

CGEM

PCVX

INCY

CELC

IMMX

BIIB

CLDX

ALNY

BMRN

ABSI

ADMA

ERAS

ARDX

KURA

RCUS

IMVT

DNTH

FDMT

CGON

VOR

MDGL

IRON

MYGN

RIGL

TNGX

JANX

Concentration curve

cumulative share of the +18.53 pt move · sorted by contribution

When they drove it

cumulative points through the period

Breadth

member returns, this period

−100%−50%0%+50%+100%+150%

From −86.23% (SION) to +185.51% (MRNA). Equal-weight, the XBI would be +13.93% vs the actual +12.30%; the gap is what cap weighting did.

By sector

point contribution · sums to +18.53 pts

-147

+18.5

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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