A global energy council forecasted the expected worldwide wind-turbine electricity generation capacity, in gigawatts (GW), for each of six consecutive...

Owning the Dataset

Table 1: Text Analysis

Table 2: Chart Analysis

Key Insights

1. Cumulative wind capacity grows steadily every year, doubling over the 6 years; even as the growth rate (%) declines, the absolute capacity increases each year.
2. The cumulative growth rate decreases from 15% to 11%, showing growth is slowing in percentage terms as the installed base gets larger.
3. The median value of the cumulative capacities (sorted: 380, 420, 480, 530, 600, 660) is 505 GW (average of 480 and 530), which would round to 500 GW as observed.
4. Yearly new installations hold steady at 50 GW for four years, then rise, reflecting possible future market or policy changes.
5. The dataset demonstrates a common 'mature market' trend: high initial growth slowing as market size increases, but absolute annual additions remain substantial.

Step-by-Step Solution

Question 1: Cumulative Growth Rate Trend

Complete Statement:

From Y1 to Y6 the graph indicates that the expected annual percent rate of growth for cumulative wind capacity will [BLANK 1].

Breaking Down the Statement

• Statement Breakdown 1:
  • Key Phrase: From Y1 to Y6
    - Meaning: Examining the entire forecast period covered by the chart, from the first to the last year shown.
    - Relation to Chart: This refers to the x-axis, which displays years Y1 through Y6.
    - Important Implications: We don't focus just on one year, but on the trend across all six years.
• Statement Breakdown 2:
  • Key Phrase: expected annual percent rate of growth for cumulative wind capacity
    - Meaning: The yearly percentage change in the total amount of wind capacity installed so far (cumulative).
    - Relation to Chart: This is represented by the dashed line on the graph, often using diamond markers.
    - Important Implications: Our attention is on the percent growth of the cumulative total, not just yearly additions.
• What is needed: The directional trend (increase, stay the same, or decrease) in cumulative growth rate from year Y1 to Y6.

Solution:

• Condensed Solution Implementation:
  Visually examine the dashed line for cumulative growth rate from Y1 to Y6.
• Necessary Data points:
  Cumulative growth rate values by year as indicated: Y1: 15%, Y2: 14%, Y3: 13%, Y4: 12%, Y5: 12%, Y6: 11%.
  • Calculations Estimations:
    Observe that values go from 15% down every year (except one repeat at 12%), ending at 11%. Thus, the rate decreases overall.
  • Comparison to Answer Choices:
    Compared to options, 'decrease' describes the trend from 15% to 11% best.

FINAL ANSWER Blank 1: decrease

Question 2: Median Cumulative Capacity

Complete Statement:

To the nearest 50 GW, the median of the expected cumulative wind capacities from Y1 to Y6 is [BLANK 2].

Breaking Down the Statement

• Statement Breakdown 1:
  • Key Phrase: median of the expected cumulative wind capacities
    - Meaning: The middle value when all six capacities are put in order.
    - Relation to Chart: Use the blue bar (or similar) for cumulative capacity for every year.
• Statement Breakdown 2:
  • Key Phrase: from Y1 to Y6
    - Meaning: We are to include all six years for the calculation.
    - Relation to Chart: Cumulative capacity numbers for Y1, Y2, Y3, Y4, Y5, and Y6.
• What is needed: The median cumulative capacity from the six yearly values, rounded to the nearest 50 GW.

Solution:

• Condensed Solution Implementation:
  List the capacities, order them, find the average of the 3rd and 4th (since there are 6 values), then round to the nearest 50 GW.
• Necessary Data points:
  Cumulative capacities: 380 GW, 420 GW, 480 GW, 530 GW, 600 GW, 660 GW.
  • Calculations Estimations:
    Median = \\((480 + 530) / 2 = 505\\) GW.
  • Comparison to Answer Choices:
    505 GW rounded to the nearest 50 GW is 500 GW, which matches the correct answer.

FINAL ANSWER Blank 2: 500 GW

Summary

Both blanks are answered using either direct visual interpretation (for the trend in growth rates) or straightforward computation (for the median). No advanced math is required: trend is visible in the dashed line, and the median requires simply averaging middle values and rounding.

Question Independence Analysis

Blank 1 (growth rate trend) and Blank 2 (median capacity value) require separate sets of information from the chart and do not influence each other. Their computations are fully independent.