Ключевые слова: 20, 80, analysis, background, big, business, color, colorful, concept, conceptual, design, different, economic, education, efficiency, effort, eighty, factor, few, figures, flat, green, house, houses, law, lay, little, management, metaphor, nobody, object, pareto, percentage, percents, presentation, principle, productivity, proportion, result, rule, size, small, sparsity, top, twenty, view, vital, yellow,