She will first analyze the historical data by separating the causes of past changes in demand into the following  (1) trend, (2) seasonality, (3) cyclicality, and (4) random fluctuation.
( She ( ( ( will first ) ( analyze ( ( ( ( ( ( the ( historical data ) ) ( by ( ( separating ( ( the causes ) ( of ( ( past changes ) ( in demand ) ) ) ) ) ( into ( ( ( ( the ( ( ( ( following ( ( -LRB- ( 1 -RRB- ) ) trend ) ) , ) ( -LRB- ( 2 -RRB- ) ) ) seasonality ) ) , ) ( -LRB- ( 3 -RRB- ) ) ) cyclicality ) ) ) ) ) , ) and ) ( -LRB- ( 4 -RRB- ) ) ) ( random fluctuation ) ) ) ) . ) )
(ROOT (S (NP (PRP She)) (VP (MD will) (ADVP (RB first)) (VP (VB analyze) (NP (NP (NP (DT the) (JJ historical) (NNS data)) (PP (IN by) (S (VP (VBG separating) (NP (NP (DT the) (NNS causes)) (PP (IN of) (NP (NP (JJ past) (NNS changes)) (PP (IN in) (NP (NN demand)))))) (PP (IN into) (NP (NP (NP (DT the) (NP (NP (JJ following) (PRN (-LRB- -LRB-) (NP (CD 1)) (-RRB- -RRB-)) (NN trend)) (, ,) (PRN (-LRB- -LRB-) (NP (CD 2)) (-RRB- -RRB-))) (NN seasonality)) (, ,) (PRN (-LRB- -LRB-) (NP (CD 3)) (-RRB- -RRB-))) (ADVP (RB cyclicality)))))))) (, ,) (CC and) (PRN (-LRB- -LRB-) (NP (CD 4)) (-RRB- -RRB-)) (NP (JJ random) (NN fluctuation))))) (. .)))
Of the 4, random fluctuation is the most problematic for analysts.
( ( Of ( the 4 ) ) ( , ( ( random fluctuation ) ( ( is ( ( the ( most problematic ) ) ( for analysts ) ) ) . ) ) ) )
(ROOT (S (PP (IN Of) (NP (DT the) (CD 4))) (, ,) (NP (JJ random) (NN fluctuation)) (VP (VBZ is) (NP (NP (DT the) (ADJP (RBS most) (JJ problematic))) (PP (IN for) (NP (NNS analysts))))) (. .)))